diff --git a/bin/is b/bin/is
index 57a4fdadf1222b025d796d0dd3e6a535ea10ecee..ff19d36ff2c67b0e3fb68997f9928200e19799f4 100755
--- a/bin/is
+++ b/bin/is
@@ -71,11 +71,11 @@ def get_images(patterns, repoman, local=True, min=None, max=None):
             ans += sorted(repoman.select_images([pattern]).items())
     # check selected images cound
     if min is not None and len(ans) < min:
-        raise Exception("%s images found. Should be at least %s" % (
+        raise Exception(u"%s images found. Should be at least %s" % (
                 len(ans), min))
     # check max selected images
     if max is not None and  len(ans) > max:
-        raise Exception("Too many selected images: %s. Max is %s" % (
+        raise Exception(u"Too many selected images: %s. Max is %s" % (
                 ", ".join([n[0] for n in ans]), max))
     for item in ans:
         if item[1] is None:
@@ -112,7 +112,7 @@ def c_build(args):
     # compute building time
     t1 = time.time()
     dt = int(t1 - t0)
-    arrow("Build time: %s" % datetime.timedelta(seconds=dt))
+    arrow(u"Build time: %s" % datetime.timedelta(seconds=dt))
 
 def c_cat(args):
     '''
@@ -164,8 +164,8 @@ def c_copy(args):
     if not args.force:
         out("You will copy the following images:")
         for img, repo in todo:
-            out("  %s/%s:%s" % (repo.config.name, img.name, img.version))
-        out("Inside repository: #l##b#%s#R#" % dstrepo.config.name)
+            out(u"  %s/%s:%s" % (repo.config.name, img.name, img.version))
+        out(u"Inside repository: #l##b#%s#R#" % dstrepo.config.name)
         if not confirm():
             raise Exception("Aborted!")
     # copy it for real
@@ -192,7 +192,7 @@ def c_del(args):
     if not args.force:
         out("You will remove the following images:")
         for img, repo in todo:
-            out("  %s/%s:%s" % (repo.config.name, img.name, img.version))
+            out(u"  %s/%s:%s" % (repo.config.name, img.name, img.version))
         if not confirm():
             raise Exception("Aborted!")
     # delete it for real
@@ -272,7 +272,7 @@ def c_install(args):
     repoman = load_repositories(args)
     image, repo = next(get_images([args.pattern], repoman, min=1, max=1))
     # Print setup information
-    arrow("Installing %s v%s" % (image.name, image.version))
+    arrow(u"Installing %s v%s" % (image.name, image.version))
     # install start time
     t0 = time.time()
     # run parser scripts with parser parser argument
@@ -286,7 +286,7 @@ def c_install(args):
         # compute building time
         t1 = time.time()
         dt = int(t1 - t0)
-        arrow("Install time: %s" % datetime.timedelta(seconds=dt))
+        arrow(u"Install time: %s" % datetime.timedelta(seconds=dt))
 
 def c_list(args):
     '''
@@ -318,8 +318,8 @@ def c_move(args):
     if not args.force:
         out("You will copy and remove the following images:")
         for img, repo in todo:
-            out("  %s/%s:%s" % (repo.config.name, img.name, img.version))
-        out("Inside repository: #l##b#%s#R#" % dstrepo.config.name)
+            out(u"  %s/%s:%s" % (repo.config.name, img.name, img.version))
+        out(u"Inside repository: #l##b#%s#R#" % dstrepo.config.name)
         if not confirm():
             raise Exception("Aborted!")
     # move it for real
@@ -679,7 +679,7 @@ def main():
                     proc.nice = options.nice
                     debug("Setting nice to %d" % options.nice)
                 except Exception:
-                    warn("Unable to nice process to %s" % options.nice)
+                    warn(u"Unable to nice process to %s" % options.nice)
             if options.ionice_class is not None:
                 try:
                     ioclassmap = {
@@ -688,10 +688,10 @@ def main():
                         "be": psutil.IOPRIO_CLASS_BE,
                         "idle": psutil.IOPRIO_CLASS_IDLE}
                     proc.set_ionice(ioclassmap[options.ionice_class], options.ionice_level)
-                    debug("Setting ionice to class %s, level %s" %
+                    debug(u"Setting ionice to class %s, level %s" %
                           (options.ionice_class, options.ionice_level))
                 except Exception:
-                    warn("Unable to ionice process to %s" % options.ionice_class)
+                    warn(u"Unable to ionice process to %s" % options.ionice_class)
         # set timeout option
         if options.timeout is not None:
             socket.setdefaulttimeout(options.timeout)
diff --git a/installsystems/config.py b/installsystems/config.py
index 877161b016086aafc8e39fe555b82b5006de1117..0bfe8e6a051c9e35c5b85605f1f815b74be7dfff 100644
--- a/installsystems/config.py
+++ b/installsystems/config.py
@@ -41,8 +41,8 @@ class ConfigFile(object):
         '''
         Return path of the best config file
         '''
-        for cf in [ os.path.join(os.path.expanduser("~/.config/installsystems/%s.conf" % name)),
-                    "/etc/installsystems/%s.conf" % name ]:
+        for cf in [ os.path.join(os.path.expanduser(u"~/.config/installsystems/%s.conf" % name)),
+                    u"/etc/installsystems/%s.conf" % name ]:
             if (os.path.isfile(cf) and os.access(cf, os.R_OK)):
                 return cf
         return None
@@ -82,7 +82,7 @@ class MainConfigFile(ConfigFile):
         if self.path is None:
             debug("No main config file to load")
             return
-        debug("Loading main config file: %s" % self.path)
+        debug(u"Loading main config file: %s" % self.path)
         try:
             cp = RawConfigParser()
             cp.read(self.path)
@@ -90,7 +90,7 @@ class MainConfigFile(ConfigFile):
             if cp.has_section(self.prefix):
                 self._config.update(cp.items(self.prefix))
         except Exception as e:
-            raise Exception("Unable load main config file %s: %s" % (self.path, e))
+            raise Exception(u"Unable load main config file %s: %s" % (self.path, e))
 
     def parse(self, namespace=None):
         '''
@@ -101,11 +101,11 @@ class MainConfigFile(ConfigFile):
         for option, value in self._config.items():
             # check option is valid
             if option not in self.valid_options.keys():
-                warn("Invalid option %s in %s, skipped" % (option, self.path))
+                warn(u"Invalid option %s in %s, skipped" % (option, self.path))
                 continue
             # we expect a string like
             if not isinstance(option, basestring):
-                raise TypeError("Invalid config parser option %s type" % option)
+                raise TypeError(u"Invalid config parser option %s type" % option)
             # smartly cast option's value
             if self.valid_options[option] is bool:
                 value = value.strip().lower() not in ("false", "no", "0", "")
@@ -170,7 +170,7 @@ class MainConfigFile(ConfigFile):
                     os.mkdir(di)
                     break
                 except Exception as e:
-                    debug("Unable to create %s: %s" % (di, e))
+                    debug(u"Unable to create %s: %s" % (di, e))
         return self._cache_path()
 
 
@@ -190,7 +190,7 @@ class RepoConfigFile(ConfigFile):
         if self.path is None:
             return
         # loading config file if exists
-        debug("Loading repository config file: %s" % self.path)
+        debug(u"Loading repository config file: %s" % self.path)
         try:
             cp = RawConfigParser()
             cp.readfp(codecs.open(self.path, "r", "utf8"))
@@ -202,7 +202,7 @@ class RepoConfigFile(ConfigFile):
                 # get all options in repo
                 self._repos.append(RepositoryConfig(rep, **dict(cp.items(rep))))
         except Exception as e:
-            raise Exception("Unable to load repository file %s: %s" % (self.path, e))
+            raise Exception(u"Unable to load repository file %s: %s" % (self.path, e))
 
     @property
     def repos(self):
diff --git a/installsystems/database.py b/installsystems/database.py
index f9dc86ee7cdabd61c95ce9bae4cc9bea6ff862de..df8df8bc6b7d4772ceddacc2208e24616c54d6fc 100644
--- a/installsystems/database.py
+++ b/installsystems/database.py
@@ -35,7 +35,7 @@ class Database(object):
             conn.commit()
             conn.close()
         except Exception as e:
-            raise Exception("Create database failed: %s" % e)
+            raise Exception(u"Create database failed: %s" % e)
         return cls(path)
 
     def __init__(self, path):
@@ -57,13 +57,13 @@ class Database(object):
             self.version = 1.0
         # we only support database v1
         if self.version >= 2.0:
-            debug("Invalid database format: %s" % self.version)
+            debug(u"Invalid database format: %s" % self.version)
             raise Exception("Invalid database format")
         # we make a query to be sure format is valid
         try:
             self.ask("SELECT * FROM image")
         except:
-            debug("Invalid database format: %s" % self.version)
+            debug(u"Invalid database format: %s" % self.version)
             raise Exception("Invalid database format")
 
     def begin(self):
diff --git a/installsystems/image.py b/installsystems/image.py
index d2131edf63899fe10ca1b672c82c1a3f65743833..c086b237cae3f33f0706d770a0c6864ba0f846d3 100644
--- a/installsystems/image.py
+++ b/installsystems/image.py
@@ -43,7 +43,7 @@ class Image(object):
         Check if @buf is a valid image name
         '''
         if re.match("^[-_\w]+$", buf) is None:
-            raise Exception("Invalid image name %s" % buf)
+            raise Exception(u"Invalid image name %s" % buf)
 
     @staticmethod
     def check_image_version(buf):
@@ -51,7 +51,7 @@ class Image(object):
         Check if @buf is a valid image version
         '''
         if re.match("^\d+$", buf) is None:
-            raise Exception("Invalid image version %s" % buf)
+            raise Exception(u"Invalid image version %s" % buf)
 
     @staticmethod
     def compare_versions(v1, v2):
@@ -86,7 +86,7 @@ class SourceImage(Image):
                 if not os.path.exists(d) or not os.path.isdir(d):
                     os.mkdir(d)
         except Exception as e:
-            raise Exception("Unable to create directory: %s: %s" % (d, e))
+            raise Exception(u"Unable to create directory: %s: %s" % (d, e))
         # create example files
         arrow("Creating examples")
         arrowlevel(1)
@@ -110,14 +110,14 @@ class SourceImage(Image):
         examples["setup"] = {"path": "setup/01-setup.py", "content": istemplate.setup}
         for name in examples:
             try:
-                arrow("Creating %s example" % name)
+                arrow(u"Creating %s example" % name)
                 expath = os.path.join(path, examples[name]["path"])
                 if not force and os.path.exists(expath):
-                    warn("%s already exists. Skipping!" % expath)
+                    warn(u"%s already exists. Skipping!" % expath)
                     continue
                 open(expath, "w").write(examples[name]["content"])
             except Exception as e:
-                raise Exception("Unable to create example file: %s" % e)
+                raise Exception(u"Unable to create example file: %s" % e)
         try:
             # setting executable rights on files in setup and parser
             arrow("Setting executable rights on scripts")
@@ -127,7 +127,7 @@ class SourceImage(Image):
                 for f in os.listdir(dpath):
                     istools.chrights(os.path.join(dpath, f), mode=0777 & ~umask)
         except Exception as e:
-            raise Exception("Unable to set rights on %s: %s" % (pf, e))
+            raise Exception(u"Unable to set rights on %s: %s" % (pf, e))
         arrowlevel(-1)
 
     def __init__(self, path):
@@ -137,14 +137,14 @@ class SourceImage(Image):
         Image.__init__(self)
         self.base_path = os.path.abspath(path)
         for pathtype in ("build", "parser", "setup", "payload"):
-            setattr(self, "%s_path" % pathtype, os.path.join(self.base_path, pathtype))
+            setattr(self, u"%s_path" % pathtype, os.path.join(self.base_path, pathtype))
         self.check_source_image()
         self.description = self.parse_description()
         self.changelog = self.parse_changelog()
         # script tarball path
-        self.image_name = "%s-%s%s" % (self.description["name"],
-                                       self.description["version"],
-                                       self.extension)
+        self.image_name = u"%s-%s%s" % (self.description["name"],
+                                        self.description["version"],
+                                        self.extension)
 
     def check_source_image(self):
         '''
@@ -153,11 +153,11 @@ class SourceImage(Image):
         for d in (self.base_path, self.build_path, self.parser_path,
                   self.setup_path, self.payload_path):
             if not os.path.exists(d):
-                raise Exception("Invalid source image: directory %s is missing" % d)
+                raise Exception(u"Invalid source image: directory %s is missing" % d)
             if not os.path.isdir(d):
-                raise Exception("Invalid source image: %s is not a directory" % d)
+                raise Exception(u"Invalid source image: %s is not a directory" % d)
             if not os.access(d, os.R_OK|os.X_OK):
-                raise Exception("Invalid source image: unable to access to %s" % d)
+                raise Exception(u"Invalid source image: unable to access to %s" % d)
         if not os.path.exists(os.path.join(self.base_path, "description")):
             raise Exception("Invalid source image: no description file")
 
@@ -196,12 +196,12 @@ class SourceImage(Image):
         # create tarball
         arrow("Creating image tarball")
         arrowlevel(1)
-        arrow("Name %s" % self.image_name)
+        arrow(u"Name %s" % self.image_name)
         try:
             try:
                 tarball = Tarball.open(self.image_name, mode="w:gz", dereference=True)
             except Exception as e:
-                raise Exception("Unable to create tarball %s: %s" % (self.image_name, e))
+                raise Exception(u"Unable to create tarball %s: %s" % (self.image_name, e))
             # add description.json
             arrow("Add description.json")
             tarball.add_str("description.json", jdescription, tarfile.REGTYPE, 0644)
@@ -231,13 +231,13 @@ class SourceImage(Image):
         '''
         ans = {}
         ans["source_path"] = os.path.join(self.payload_path, name)
-        ans["dest_path"] = "%s-%s%s" % (self.description["name"],
-                                        name,
-                                        Payload.extension)
-        ans["link_path"] = "%s-%s-%s%s" % (self.description["name"],
-                                           self.description["version"],
-                                           name,
-                                           Payload.extension)
+        ans["dest_path"] = u"%s-%s%s" % (self.description["name"],
+                                         name,
+                                         Payload.extension)
+        ans["link_path"] = u"%s-%s-%s%s" % (self.description["name"],
+                                            self.description["version"],
+                                            name,
+                                            Payload.extension)
         source_stat = os.stat(ans["source_path"])
         ans["isdir"] = stat.S_ISDIR(source_stat.st_mode)
         ans["uid"] = source_stat.st_uid
@@ -292,7 +292,7 @@ class SourceImage(Image):
                     os.unlink(paydesc["link_path"])
                 os.symlink(paydesc["dest_path"], paydesc["link_path"])
             except Exception as e:
-                raise Exception("Unable to create payload %s: %s" % (payload_name, e))
+                raise Exception(u"Unable to create payload %s: %s" % (payload_name, e))
 
     def create_payload_tarball(self, tar_path, data_path):
         '''
@@ -322,7 +322,7 @@ class SourceImage(Image):
                 raise Exception("Tar return is not zero")
             # check compressor return 0
             if p_comp.wait() != 0:
-                raise Exception("Compressor %s return is not zero" % a_comp[0])
+                raise Exception(u"Compressor %s return is not zero" % a_comp[0])
         except (SystemExit, KeyboardInterrupt):
             if os.path.exists(tar_path):
                 os.unlink(tar_path)
@@ -351,7 +351,7 @@ class SourceImage(Image):
             f_dst.close()
             # check compressor return 0
             if p_comp.wait() != 0:
-                raise Exception("Compressor %s return is not zero" % a_comp[0])
+                raise Exception(u"Compressor %s return is not zero" % a_comp[0])
         except (SystemExit, KeyboardInterrupt):
             if os.path.exists(dest):
                 os.unlink(dest)
@@ -362,7 +362,7 @@ class SourceImage(Image):
         Add scripts inside a directory into a tarball
         '''
         basedirectory = os.path.basename(directory)
-        arrow("Add %s scripts" % basedirectory)
+        arrow(u"Add %s scripts" % basedirectory)
         arrowlevel(1)
         # adding base directory
         ti = tarball.gettarinfo(directory, arcname=basedirectory)
@@ -377,7 +377,7 @@ class SourceImage(Image):
             ti.uid = ti.gid = 0
             ti.uname = ti.gname = "root"
             tarball.addfile(ti, open(fp, "rb"))
-            arrow("%s added" % fn)
+            arrow(u"%s added" % fn)
         arrowlevel(-1)
 
     def check_scripts(self, directory):
@@ -385,7 +385,7 @@ class SourceImage(Image):
         Check if scripts inside a directory can be compiled
         '''
         basedirectory = os.path.basename(directory)
-        arrow("Checking %s scripts" % basedirectory)
+        arrow(u"Checking %s scripts" % basedirectory)
         arrowlevel(1)
         # checking each file
         for fp, fn in self.select_scripts(directory):
@@ -400,7 +400,7 @@ class SourceImage(Image):
         Execute script inside a directory
         Return a list of payload to force rebuild
         '''
-        arrow("Run %s scripts" % os.path.basename(script_directory))
+        arrow(u"Run %s scripts" % os.path.basename(script_directory))
         rebuild_list = []
         cwd = os.getcwd()
         arrowlevel(1)
@@ -412,7 +412,7 @@ class SourceImage(Image):
             try:
                 o_scripts = compile(open(fp, "r").read(), fn, "exec")
             except Exception as e:
-                raise Exception("Unable to compile %s fail: %s" %
+                raise Exception(u"Unable to compile %s fail: %s" %
                                 (fn, e))
             # define execution context
             gl = {"rebuild": rebuild_list,
@@ -421,7 +421,7 @@ class SourceImage(Image):
             try:
                 exec o_scripts in gl
             except Exception as e:
-                raise Exception("Execution script %s fail: %s" %
+                raise Exception(u"Execution script %s fail: %s" %
                                 (fn, e))
             arrowlevel(level=old_level)
         os.chdir(cwd)
@@ -510,7 +510,7 @@ class SourceImage(Image):
             if self.compare_versions(installsystems.version, d["is_min_version"]) < 0:
                 raise Exception("Minimum Installsystems version not satisfied")
         except Exception as e:
-            raise Exception("Bad description: %s" % e)
+            raise Exception(u"Bad description: %s" % e)
         return d
 
     def parse_changelog(self):
@@ -528,7 +528,7 @@ class SourceImage(Image):
         try:
             cl = Changelog(fo.read())
         except Exception as e:
-            raise Exception("Bad changelog: %s" % e)
+            raise Exception(u"Bad changelog: %s" % e)
         return cl
 
     @property
@@ -550,10 +550,10 @@ class PackageImage(Image):
         '''
         Diff two packaged images
         '''
-        arrow("Difference from images #y#%s v%s#R# to #r#%s v%s#R#:" % (pkg1.name,
-                                                                       pkg1.version,
-                                                                       pkg2.name,
-                                                                       pkg2.version))
+        arrow(u"Difference from images #y#%s v%s#R# to #r#%s v%s#R#:" % (pkg1.name,
+                                                                         pkg1.version,
+                                                                         pkg2.name,
+                                                                         pkg2.version))
         # Extract images for diff scripts files
         fromfiles = set(pkg1._tarball.getnames(re_pattern="(parser|setup)/.*"))
         tofiles = set(pkg2._tarball.getnames(re_pattern="(parser|setup)/.*"))
@@ -577,11 +577,11 @@ class PackageImage(Image):
                                              fromfile=fromfile, tofile=tofile):
                 # coloring diff
                 if line.startswith("+"):
-                   out("#g#%s#R#" % line, endl="")
+                   out(u"#g#%s#R#" % line, endl="")
                 elif line.startswith("-"):
-                   out("#r#%s#R#" % line, endl="")
+                   out(u"#r#%s#R#" % line, endl="")
                 elif line.startswith("@@"):
-                   out("#c#%s#R#" % line, endl="")
+                   out(u"#c#%s#R#" % line, endl="")
                 else:
                    out(line, endl="")
 
@@ -611,17 +611,17 @@ class PackageImage(Image):
             memfile.seek(0)
             self._tarball = Tarball.open(fileobj=memfile, mode='r:gz')
         except Exception as e:
-            raise Exception("Unable to open image %s: %s" % (path, e))
+            raise Exception(u"Unable to open image %s: %s" % (path, e))
         self._metadata = self.read_metadata()
         # print info
-        arrow("Image %s v%s loaded" % (self.name, self.version))
-        arrow("Author: %s" % self.author, 1)
-        arrow("Date: %s" % istools.time_rfc2822(self.date), 1)
+        arrow(u"Image %s v%s loaded" % (self.name, self.version))
+        arrow(u"Author: %s" % self.author, 1)
+        arrow(u"Date: %s" % istools.time_rfc2822(self.date), 1)
         # build payloads info
         self.payload = {}
         for pname, pval in self._metadata["payload"].items():
-            pfilename = "%s-%s%s" % (self.filename[:-len(Image.extension)],
-                                     pname, Payload.extension)
+            pfilename = u"%s-%s%s" % (self.filename[:-len(Image.extension)],
+                                      pname, Payload.extension)
             if self.md5name:
                 ppath = os.path.join(self.base_path,
                                      self._metadata["payload"][pname]["md5"])
@@ -642,7 +642,7 @@ class PackageImage(Image):
         '''
         Return image filename
         '''
-        return "%s-%s%s" % (self.name, self.version, self.extension)
+        return u"%s-%s%s" % (self.name, self.version, self.extension)
 
     def read_metadata(self):
         '''
@@ -655,7 +655,7 @@ class PackageImage(Image):
             if float(img_format) >= math.floor(float(self.format)) + 1.0:
                 raise Exception()
         except:
-            raise Exception("Invalid image format %s" % img_format)
+            raise Exception(u"Invalid image format %s" % img_format)
         desc["format"] = img_format
         # check description
         try:
@@ -670,7 +670,7 @@ class PackageImage(Image):
             if self.compare_versions(installsystems.version, desc["is_min_version"]) < 0:
                 raise Exception("Minimum Installsystems version not satisfied")
         except Exception as e:
-            raise Exception("Invalid description: %s" % e)
+            raise Exception(u"Invalid description: %s" % e)
         # try to load changelog
         try:
             img_changelog = self._tarball.get_str("changelog")
@@ -678,7 +678,7 @@ class PackageImage(Image):
         except KeyError:
             desc["changelog"] = Changelog("")
         except Exception as e:
-            warn("Invalid changelog: %s" % e)
+            warn(u"Invalid changelog: %s" % e)
         return desc
 
     def show(self, o_verbose=False, o_changelog=False, o_json=False):
@@ -688,27 +688,27 @@ class PackageImage(Image):
         if o_json:
             out(json.dumps(self._metadata))
         else:
-            out('#light##yellow#Name:#reset# %s' % self.name)
-            out('#light##yellow#Version:#reset# %s' % self.version)
-            out('#yellow#Date:#reset# %s' % istools.time_rfc2822(self.date))
-            out('#yellow#Description:#reset# %s' % self.description)
-            out('#yellow#Author:#reset# %s' % self.author)
+            out(u'#light##yellow#Name:#reset# %s' % self.name)
+            out(u'#light##yellow#Version:#reset# %s' % self.version)
+            out(u'#yellow#Date:#reset# %s' % istools.time_rfc2822(self.date))
+            out(u'#yellow#Description:#reset# %s' % self.description)
+            out(u'#yellow#Author:#reset# %s' % self.author)
             if o_verbose:
                 # field is_build_version is new in version 5. I can be absent.
-                try: out('#yellow#IS build version:#reset# %s' % self.is_build_version)
+                try: out(u'#yellow#IS build version:#reset# %s' % self.is_build_version)
                 except AttributeError: pass
                 # field is_min_version is new in version 5. I can be absent.
-                try: out('#yellow#IS minimum version:#reset# %s' % self.is_min_version)
+                try: out(u'#yellow#IS minimum version:#reset# %s' % self.is_min_version)
                 except AttributeError: pass
-            out('#yellow#MD5:#reset# %s' % self.md5)
+            out(u'#yellow#MD5:#reset# %s' % self.md5)
             if o_verbose:
                 payloads = self.payload
                 for payload_name in payloads:
                     payload = payloads[payload_name]
-                    out('#light##yellow#Payload:#reset# %s' % payload_name)
-                    out('  #yellow#Date:#reset# %s' % istools.time_rfc2822(payload.mtime))
-                    out('  #yellow#Size:#reset# %s' % (istools.human_size(payload.size)))
-                    out('  #yellow#MD5:#reset# %s' % payload.md5)
+                    out(u'#light##yellow#Payload:#reset# %s' % payload_name)
+                    out(u'  #yellow#Date:#reset# %s' % istools.time_rfc2822(payload.mtime))
+                    out(u'  #yellow#Size:#reset# %s' % (istools.human_size(payload.size)))
+                    out(u'  #yellow#MD5:#reset# %s' % payload.md5)
             # display image content
             out('#light##yellow#Content:#reset#')
             self._tarball.list(o_verbose)
@@ -728,9 +728,9 @@ class PackageImage(Image):
         fo.consume()
         fo.close()
         if self.size != fo.read_size:
-            raise Exception("Invalid size of image %s" % self.name)
+            raise Exception(u"Invalid size of image %s" % self.name)
         if self.md5 != fo.md5:
-            raise Exception("Invalid MD5 of image %s" % self.name)
+            raise Exception(u"Invalid MD5 of image %s" % self.name)
         # check payloads
         for pay_name, pay_obj in self.payload.items():
             arrow(pay_name)
@@ -743,7 +743,7 @@ class PackageImage(Image):
         '''
         filelist = self._tarball.getnames(glob_pattern=filename, dir=False)
         if len(filelist) == 0:
-            warn("No file matching %s" % filename)
+            warn(u"No file matching %s" % filename)
         for filename in filelist:
             arrow(filename)
             out(self._tarball.get_str(filename))
@@ -759,27 +759,27 @@ class PackageImage(Image):
         if image:
             dest = os.path.join(directory, self.filename)
             if not force and os.path.exists(dest):
-                raise Exception("Image destination already exists: %s" % dest)
+                raise Exception(u"Image destination already exists: %s" % dest)
             # some display
-            arrow("Downloading image in %s" % directory)
-            debug("Downloading %s from %s" % (self.filename, self.path))
+            arrow(u"Downloading image in %s" % directory)
+            debug(u"Downloading %s from %s" % (self.filename, self.path))
             # open source
             fs = PipeFile(self.path, progressbar=True)
             # check if announced file size is good
             if fs.size is not None and self.size != fs.size:
-                raise Exception("Downloading image %s failed: Invalid announced size" % self.name)
+                raise Exception(u"Downloading image %s failed: Invalid announced size" % self.name)
             # open destination
             fd = open(self.filename, "wb")
             fs.consume(fd)
             fs.close()
             fd.close()
             if self.size != fs.consumed_size:
-                raise Exception("Download image %s failed: Invalid size" % self.name)
+                raise Exception(u"Download image %s failed: Invalid size" % self.name)
             if self.md5 != fs.md5:
-                raise Exception("Download image %s failed: Invalid MD5" % self.name)
+                raise Exception(u"Download image %s failed: Invalid MD5" % self.name)
         if payload:
             for payname in self.payload:
-                arrow("Downloading payload %s in %s" % (payname, directory))
+                arrow(u"Downloading payload %s in %s" % (payname, directory))
                 self.payload[payname].info
                 self.payload[payname].download(directory, force=force)
 
@@ -790,17 +790,17 @@ class PackageImage(Image):
         # check validity of dest
         if os.path.exists(directory):
             if not os.path.isdir(directory):
-                raise Exception("Destination %s is not a directory" % directory)
+                raise Exception(u"Destination %s is not a directory" % directory)
             if not force and len(os.listdir(directory)) > 0:
-                raise Exception("Directory %s is not empty (need force)" % directory)
+                raise Exception(u"Directory %s is not empty (need force)" % directory)
         else:
             istools.mkdir(directory)
         # extract content
-        arrow("Extracting image in %s" % directory)
+        arrow(u"Extracting image in %s" % directory)
         self._tarball.extractall(directory)
         # generate description file from description.json
         if gendescription:
-            arrow("Generating description file in %s" % directory)
+            arrow(u"Generating description file in %s" % directory)
             with open(os.path.join(directory, "description"), "w") as f:
                 f.write((istemplate.description % self._metadata).encode('utf-8'))
         # launch payload extraction
@@ -809,7 +809,7 @@ class PackageImage(Image):
                 # here we need to decode payname which is in unicode to escape
                 # tarfile to encode filename of file inside tarball inside unicode
                 dest = os.path.join(directory, "payload", payname.encode("utf-8"))
-                arrow("Extracting payload %s in %s" % (payname, dest))
+                arrow(u"Extracting payload %s in %s" % (payname, dest))
                 self.payload[payname].extract(dest, force=force)
 
     def run_parser(self, **kwargs):
@@ -828,7 +828,7 @@ class PackageImage(Image):
         '''
         Run scripts in a tarball directory
         '''
-        arrow("Run %s scripts" % directory)
+        arrow(u"Run %s scripts" % directory)
         arrowlevel(1)
         # get list of parser scripts
         l_scripts = self._tarball.getnames(re_pattern="%s/.*\.py" % directory)
@@ -842,13 +842,13 @@ class PackageImage(Image):
             try:
                 s_scripts = self._tarball.get_str(n_scripts)
             except Exception as e:
-                raise Exception("Extracting script %s fail: %s" %
+                raise Exception(u"Extracting script %s fail: %s" %
                                 (n_scripts, e))
             # compile source code
             try:
                 o_scripts = compile(s_scripts, n_scripts, "exec")
             except Exception as e:
-                raise Exception("Unable to compile %s fail: %s" %
+                raise Exception(u"Unable to compile %s fail: %s" %
                                 (n_scripts, e))
             # define execution context
             gl = {}
@@ -859,7 +859,7 @@ class PackageImage(Image):
             try:
                 exec o_scripts in gl
             except Exception as e:
-                raise Exception("Execution script %s fail: %s" %
+                raise Exception(u"Execution script %s fail: %s" %
                                 (n_scripts, e))
             arrowlevel(level=old_level)
         arrowlevel(-1)
@@ -887,14 +887,14 @@ class Payload(object):
 
     def __getattr__(self, name):
         # get all value with an understance as if there is no underscore
-        if hasattr(self, "_%s" % name):
-            return getattr(self, "_%s" % name)
+        if hasattr(self, u"_%s" % name):
+            return getattr(self, u"_%s" % name)
         raise AttributeError
 
     def __setattr__(self, name, value):
         # set all value which exists have no underscore, but where underscore exists
         if name in self.legit_attr:
-            object.__setattr__(self, "_%s" % name, value)
+            object.__setattr__(self, u"_%s" % name, value)
         else:
             object.__setattr__(self, name, value)
 
@@ -993,9 +993,9 @@ class Payload(object):
         fileobj.consume()
         fileobj.close()
         if self._size != fileobj.read_size:
-            raise Exception("Invalid size of payload %s" % self.name)
+            raise Exception(u"Invalid size of payload %s" % self.name)
         if self._md5 != fileobj.md5:
-            raise Exception("Invalid MD5 of payload %s" % self._md5)
+            raise Exception(u"Invalid MD5 of payload %s" % self._md5)
 
     def download(self, dest, force=False):
         '''
@@ -1010,15 +1010,15 @@ class Payload(object):
         # check validity of dest
         if os.path.exists(dest):
             if os.path.isdir(dest):
-                raise Exception("Destination %s is a directory" % dest)
+                raise Exception(u"Destination %s is a directory" % dest)
             if not force:
-                raise Exception("File %s already exists" % dest)
+                raise Exception(u"File %s already exists" % dest)
         # Open remote file
-        debug("Downloading payload %s from %s" % (self.filename, self.path))
+        debug(u"Downloading payload %s from %s" % (self.filename, self.path))
         fs = PipeFile(self.path, progressbar=True)
         # check if announced file size is good
         if fs.size is not None and self.size != fs.size:
-            raise Exception("Downloading payload %s failed: Invalid announced size" %
+            raise Exception(u"Downloading payload %s failed: Invalid announced size" %
                             self.name)
         fd = open(dest, "wb")
         fs.consume(fd)
@@ -1027,9 +1027,9 @@ class Payload(object):
         fd.close()
         # checking download size
         if self.size != fs.read_size:
-            raise Exception("Downloading payload %s failed: Invalid size" % self.name)
+            raise Exception(u"Downloading payload %s failed: Invalid size" % self.name)
         if self.md5 != fs.md5:
-            raise Exception("Downloading payload %s failed: Invalid MD5" % self.name)
+            raise Exception(u"Downloading payload %s failed: Invalid MD5" % self.name)
 
     def extract(self, dest, force=False, filelist=None):
         '''
@@ -1043,7 +1043,7 @@ class Payload(object):
             else:
                 self.extract_file(dest, force=force)
         except Exception as e:
-            raise Exception("Extracting payload %s failed: %s" % (self.name, e))
+            raise Exception(u"Extracting payload %s failed: %s" % (self.name, e))
 
     def extract_tar(self, dest, force=False, filelist=None):
         '''
@@ -1053,19 +1053,19 @@ class Payload(object):
         # check validity of dest
         if os.path.exists(dest):
             if not os.path.isdir(dest):
-                raise Exception("Destination %s is not a directory" % dest)
+                raise Exception(u"Destination %s is not a directory" % dest)
             if not force and len(os.listdir(dest)) > 0:
-                raise Exception("Directory %s is not empty (need force)" % dest)
+                raise Exception(u"Directory %s is not empty (need force)" % dest)
         else:
             istools.mkdir(dest)
         # try to open payload file
         try:
             fo = PipeFile(self.path, progressbar=True)
         except Exception as e:
-            raise Exception("Unable to open %s" % self.path)
+            raise Exception(u"Unable to open %s" % self.path)
         # check if announced file size is good
         if fo.size is not None and self.size != fo.size:
-            raise Exception("Invalid announced size on %s" % self.path)
+            raise Exception(u"Invalid announced size on %s" % self.path)
         # get compressor argv (first to escape file creation if not found)
         a_comp = istools.get_compressor_path(self.compressor, compress=False)
         a_tar = ["tar", "--extract", "--numeric-owner", "--ignore-zeros",
@@ -1093,7 +1093,7 @@ class Payload(object):
         p_comp.stdin.close()
         # check compressor return 0
         if p_comp.wait() != 0:
-            raise Exception("Compressor %s return is not zero" % a_comp[0])
+            raise Exception(u"Compressor %s return is not zero" % a_comp[0])
         # check tar return 0
         if p_tar.wait() != 0:
             raise Exception("Tar return is not zero")
@@ -1112,24 +1112,24 @@ class Payload(object):
         # check validity of dest
         if os.path.exists(dest):
             if os.path.isdir(dest):
-                raise Exception("Destination %s is a directory" % dest)
+                raise Exception(u"Destination %s is a directory" % dest)
             if not force:
-                raise Exception("File %s already exists" % dest)
+                raise Exception(u"File %s already exists" % dest)
         # get compressor argv (first to escape file creation if not found)
         a_comp = istools.get_compressor_path(self.compressor, compress=False)
         # try to open payload file (source)
         try:
             f_src = PipeFile(self.path, "r", progressbar=True)
         except Exception as e:
-            raise Exception("Unable to open payload file %s: %s" % (self.path, e))
+            raise Exception(u"Unable to open payload file %s: %s" % (self.path, e))
         # check if announced file size is good
         if f_src.size is not None and self.size != f_src.size:
-            raise Exception("Invalid announced size on %s" % self.path)
+            raise Exception(u"Invalid announced size on %s" % self.path)
         # opening destination
         try:
             f_dst = open(dest, "wb")
         except Exception as e:
-            raise Exception("Unable to open destination file %s: %s" % (dest, e))
+            raise Exception(u"Unable to open destination file %s: %s" % (dest, e))
         # run compressor process
         p_comp = subprocess.Popen(a_comp, shell=False, close_fds=True,
                                   stdin=subprocess.PIPE, stdout=f_dst)
@@ -1149,7 +1149,7 @@ class Payload(object):
         p_comp.stdin.close()
         # check compressor return 0
         if p_comp.wait() != 0:
-            raise Exception("Compressor %s return is not zero" % a_comp[0])
+            raise Exception(u"Compressor %s return is not zero" % a_comp[0])
         # settings file orginal rights
         istools.chrights(dest, self.uid, self.gid, self.mode, self.mtime)
 
@@ -1209,6 +1209,6 @@ class Changelog(dict):
         '''
         Display a version content
         '''
-        out('  #yellow#Version:#reset# %s' % version)
+        out(u'  #yellow#Version:#reset# %s' % version)
         for line in self[version]:
-            out("    %s" % line)
+            out(u"    %s" % line)
diff --git a/installsystems/printer.py b/installsystems/printer.py
index cb3a674eb81387a74c117f2a0205a6fead2fae52..925d8242443e7e42e34b35d0778935a2ad9fb485 100644
--- a/installsystems/printer.py
+++ b/installsystems/printer.py
@@ -71,29 +71,29 @@ def err(message, fd=sys.stderr, endl=os.linesep):
     out(message, fd, endl)
 
 def fatal(message, quit=True, fd=sys.stderr, endl=os.linesep):
-    out("#light##red#Fatal:#reset# #red#%s#reset#" % message, fd, endl)
+    out(u"#light##red#Fatal:#reset# #red#%s#reset#" % message, fd, endl)
     if sys.exc_info()[0] is not None and installsystems.verbosity > 1:
         raise
     if quit:
         os._exit(21)
 
 def error(message, quit=True, fd=sys.stderr, endl=os.linesep):
-    out("#light##red#Error:#reset# #red#%s#reset#" % message, fd, endl)
+    out(u"#light##red#Error:#reset# #red#%s#reset#" % message, fd, endl)
     if sys.exc_info()[0] is not None and installsystems.verbosity > 1:
         raise
     if quit:
         exit(42)
 
 def warn(message, fd=sys.stderr, endl=os.linesep):
-    out("#light##yellow#Warning:#reset# #yellow#%s#reset#" % message, fd, endl)
+    out(u"#light##yellow#Warning:#reset# #yellow#%s#reset#" % message, fd, endl)
 
 def info(message, fd=sys.stderr, endl=os.linesep):
     if installsystems.verbosity > 0:
-        out("#light#Info:#reset# %s" % message, fd, endl)
+        out(u"#light#Info:#reset# %s" % message, fd, endl)
 
 def debug(message, fd=sys.stderr, endl=os.linesep):
     if installsystems.verbosity > 1:
-        out("#light##black#%s#reset#" % message, fd, endl)
+        out(u"#light##black#%s#reset#" % message, fd, endl)
 
 def arrowlevel(inc=None, level=None):
     global _arrow_level
@@ -110,13 +110,13 @@ def arrow(message, inclevel=None, level=None, fd=sys.stdout, endl=os.linesep):
     # define new level
     old_level = arrowlevel(inc=inclevel, level=level)
     if _arrow_level == 1:
-        out("#light##red#=>#reset# %s" % message, fd=fd, endl=endl)
+        out(u"#light##red#=>#reset# %s" % message, fd=fd, endl=endl)
     elif _arrow_level == 2:
-        out(" #light##yellow#=>#reset# %s" % message, fd=fd, endl=endl)
+        out(u" #light##yellow#=>#reset# %s" % message, fd=fd, endl=endl)
     elif _arrow_level == 3:
-        out("  #light##blue#=>#reset# %s" % message, fd=fd, endl=endl)
+        out(u"  #light##blue#=>#reset# %s" % message, fd=fd, endl=endl)
     elif _arrow_level == 4:
-        out("   #light##green#=>#reset# %s" % message, fd=fd, endl=endl)
+        out(u"   #light##green#=>#reset# %s" % message, fd=fd, endl=endl)
     # restore old on one shot level
     arrowlevel(level = old_level)
 
@@ -134,5 +134,5 @@ def confirm(message=None, ans=None, fd=sys.stdout, endl=""):
     if ans is None:
         ans = "yes"
     if message is None:
-        message = "#u##l##w#Are you sure?#R# (%s) " % ans
+        message = u"#u##l##w#Are you sure?#R# (%s) " % ans
     return ask(message, fd, endl) == ans
diff --git a/installsystems/repository.py b/installsystems/repository.py
index 2c534b31f6a168029bd84a837f25990bc6ae7e77..301948492da8acc130eb76993f57a0aa18784c76 100644
--- a/installsystems/repository.py
+++ b/installsystems/repository.py
@@ -39,7 +39,7 @@ class Repository(object):
         Raise exception is repository name is invalid
         '''
         if not Repository.is_repository_name(name):
-            raise Exception("Invalid repository name %s" % name)
+            raise Exception(u"Invalid repository name %s" % name)
         return name
 
     @staticmethod
@@ -50,7 +50,7 @@ class Repository(object):
         '''
         x = re.match(u"^(?:([^/:]+)/)?([^/:]+)?(?::v?([^/:]+)?)?$", path)
         if x is None:
-            raise Exception("invalid image path: %s" % path)
+            raise Exception(u"invalid image path: %s" % path)
         return x.group(1, 2, 3)
 
     @staticmethod
@@ -67,8 +67,8 @@ class Repository(object):
         '''
         Comptue a diff between two repositories
         '''
-        arrow("Diff between repositories #y#%s#R# and #g#%s#R#" % (repo1.config.name,
-                                                                   repo2.config.name))
+        arrow(u"Diff between repositories #y#%s#R# and #g#%s#R#" % (repo1.config.name,
+                                                                    repo2.config.name))
         # Get info from databases
         i_dict1 = dict((b[0], b[1:]) for b in repo1.db.ask(
                 "SELECT md5, name, version FROM image").fetchall())
@@ -105,10 +105,10 @@ class Repository(object):
             try:
                 self.db = Database(config.dbpath)
             except:
-                debug("Unable to load database %s" % config.dbpath)
+                debug(u"Unable to load database %s" % config.dbpath)
                 self.config.offline = True
         if self.config.offline:
-            debug("Repository %s is offline" % config.name)
+            debug(u"Repository %s is offline" % config.name)
 
     def __getattribute__(self, name):
         '''
@@ -122,7 +122,7 @@ class Repository(object):
             return object.__getattribute__(self, name)
         # if no db (not init or not accessible) raise error
         if config.offline:
-            raise Exception("Repository %s is offline" % config.name)
+            raise Exception(u"Repository %s is offline" % config.name)
         return object.__getattribute__(self, name)
 
     @property
@@ -139,19 +139,19 @@ class Repository(object):
         config = self.config
         # check local repository
         if not self.local:
-            raise Exception("Repository creation must be local")
+            raise Exception(u"Repository creation must be local")
         # create base directories
         arrow("Creating base directories")
         arrowlevel(1)
         # creating local directory
         try:
             if os.path.exists(config.path):
-                arrow("%s already exists" % config.path)
+                arrow(u"%s already exists" % config.path)
             else:
                 istools.mkdir(config.path, config.uid, config.gid, config.dmod)
-                arrow("%s directory created" % config.path)
+                arrow(u"%s directory created" % config.path)
         except Exception as e:
-            raise Exception("Unable to create directory %s: %s" % (config.path, e))
+            raise Exception(u"Unable to create directory %s: %s" % (config.path, e))
         arrowlevel(-1)
         # create database
         d = Database.create(config.dbpath)
@@ -170,14 +170,14 @@ class Repository(object):
         '''
         # check local repository
         if not self.local:
-            raise Exception("Repository addition must be local")
+            raise Exception(u"Repository addition must be local")
         try:
             arrow("Updating last file")
             last_path = os.path.join(self.config.path, self.config.lastname)
             open(last_path, "w").write("%s\n" % int(time.time()))
             istools.chrights(last_path, self.config.uid, self.config.gid, self.config.fmod)
         except Exception as e:
-            raise Exception("Update last file failed: %s" % e)
+            raise Exception(u"Update last file failed: %s" % e)
 
     def last(self, name):
         '''
@@ -197,19 +197,19 @@ class Repository(object):
         '''
         # check local repository
         if not self.local:
-            raise Exception("Repository addition must be local")
+            raise Exception(u"Repository addition must be local")
         # cannot add already existant image
         if self.has(image.name, image.version):
-            raise Exception("Image already in database, delete first!")
+            raise Exception(u"Image already in database, delete first!")
         # adding file to repository
         arrow("Copying images and payload")
         for obj in [ image ] + image.payload.values():
             dest = os.path.join(self.config.path, obj.md5)
             basesrc = os.path.basename(obj.path)
             if os.path.exists(dest):
-                arrow("Skipping %s: already exists" % basesrc, 1)
+                arrow(u"Skipping %s: already exists" % basesrc, 1)
             else:
-                arrow("Adding %s (%s)" % (basesrc, obj.md5), 1)
+                arrow(u"Adding %s (%s)" % (basesrc, obj.md5), 1)
                 dfo = open(dest, "wb")
                 sfo = PipeFile(obj.path, "r", progressbar=True)
                 sfo.consume(dfo)
@@ -272,7 +272,7 @@ class Repository(object):
         '''
         # Check if the repo is local
         if not self.local:
-            raise Exception("Repository must be local")
+            raise Exception(u"Repository must be local")
         local_files = set(os.listdir(self.config.path))
         local_files.remove(self.config.dbname)
         local_files.remove(self.config.lastname)
@@ -302,7 +302,7 @@ class Repository(object):
         '''
         # Check if the repo is local
         if not self.local:
-            raise Exception("Repository must be local")
+            raise Exception(u"Repository must be local")
         allmd5 = set(self.getallmd5())
         repofiles = set(os.listdir(self.config.path)) - set([self.config.dbname, self.config.lastname])
         dirtyfiles = repofiles - allmd5
@@ -313,19 +313,19 @@ class Repository(object):
                 arrow(f, 1)
             # ask confirmation
             if not force and not confirm("Remove dirty files? (yes) "):
-                raise Exception("Aborted!")
+                raise Exception(u"Aborted!")
             # start cleaning
             arrow("Cleaning")
             for f in dirtyfiles:
                 p = os.path.join(self.config.path, f)
-                arrow("Removing %s" % p, 1)
+                arrow(u"Removing %s" % p, 1)
                 try:
                     if os.path.isdir(p):
                         os.rmdir(p)
                     else:
                         os.unlink(p)
                 except:
-                    warn("Removing %s failed" % p)
+                    warn(u"Removing %s failed" % p)
         else:
             arrow("Nothing to clean")
 
@@ -335,7 +335,7 @@ class Repository(object):
         '''
         # check local repository
         if not self.local:
-            raise Exception("Repository deletion must be local")
+            raise Exception(u"Repository deletion must be local")
         # get md5 of files related to images (exception is raised if not exists
         md5s = self.getmd5(name, version)
         # cleaning db (must be done before cleaning)
@@ -388,7 +388,7 @@ class Repository(object):
             if md5 not in res:
                 res[md5] = {"size": payload[1], "isdir": payload[2], "images": {}}
             # add image to list
-            imgpath = "%s/%s:%s" % (self.config.name, payload[3], payload[4])
+            imgpath = u"%s/%s:%s" % (self.config.name, payload[3], payload[4])
             res[md5]["images"][imgpath] = {"repo": self.config.name,
                                            "imgname": payload[3],
                                            "imgver": payload[4],
@@ -404,12 +404,12 @@ class Repository(object):
                               WHERE name LIKE ? OR\
                               description LIKE ? OR\
                               author LIKE ?",
-                             tuple( ["%%%s%%" % pattern ] * 3)
+                             tuple( [u"%%%s%%" % pattern ] * 3)
                              ).fetchall()
         for name, version, author, description in images:
-            arrow("%s v%s" % (name, version), 1)
-            out("   #yellow#Author:#reset# %s" % author)
-            out("   #yellow#Description:#reset# %s" % description)
+            arrow(u"%s v%s" % (name, version), 1)
+            out(u"   #yellow#Author:#reset# %s" % author)
+            out(u"   #yellow#Description:#reset# %s" % description)
 
     def _remove_file(self, filename):
         '''
@@ -418,14 +418,14 @@ class Repository(object):
         # check existance in table image
         have = False
         for table in ("image", "payload"):
-            have = have or  self.db.ask("SELECT md5 FROM %s WHERE md5 = ? LIMIT 1" % table,
+            have = have or  self.db.ask(u"SELECT md5 FROM %s WHERE md5 = ? LIMIT 1" % table,
                                         (filename,)).fetchone() is not None
         # if no reference, delete!
         if not have:
-            arrow("%s, deleted" % filename)
+            arrow(u"%s, deleted" % filename)
             os.unlink(os.path.join(self.config.path, filename))
         else:
-            arrow("%s, skipped" % filename)
+            arrow(u"%s, skipped" % filename)
 
     def has(self, name, version):
         '''
@@ -441,30 +441,30 @@ class Repository(object):
         if version is None:
             version = self.last(name)
             if version < 0:
-                raise Exception("Unable to find image %s in %s" % (name,
-                                                                   self.config.name))
+                raise Exception(u"Unable to find image %s in %s" % (name,
+                                                                    self.config.name))
         # get file md5 from db
         r = self.db.ask("select md5 from image where name = ? and version = ? limit 1",
                         (name, version)).fetchone()
         if r is None:
-            raise Exception("Unable to find image %s v%s in %s" % (name, version,
-                                                                   self.config.name))
+            raise Exception(u"Unable to find image %s v%s in %s" % (name, version,
+                                                                    self.config.name))
         path = os.path.join(self.config.path, r[0])
         # getting the file
-        arrow("Loading image %s v%s from repository %s" % (name,
-                                                           version,
-                                                           self.config.name))
+        arrow(u"Loading image %s v%s from repository %s" % (name,
+                                                            version,
+                                                            self.config.name))
         memfile = cStringIO.StringIO()
         try:
             fo = PipeFile(path, "r")
             fo.consume(memfile)
             fo.close()
         except Exception as e:
-            raise Exception("Loading image %s v%s failed: %s" % (name, version, e))
+            raise Exception(u"Loading image %s v%s failed: %s" % (name, version, e))
         memfile.seek(0)
         pkg = PackageImage(path, fileobj=memfile, md5name=True)
         if pkg.md5 != r[0]:
-            raise Exception("Image MD5 verification failure")
+            raise Exception(u"Image MD5 verification failure")
         return pkg
 
     def getmd5(self, name, version):
@@ -476,7 +476,7 @@ class Repository(object):
         a = self.db.ask("SELECT md5 FROM image WHERE name = ? AND version = ? LIMIT 1",
                         (name,version)).fetchone()
         if a is None:
-            raise Exception("No such image %s version %s" % (name, version))
+            raise Exception(u"No such image %s version %s" % (name, version))
         b = self.db.ask("SELECT md5 FROM payload WHERE image_md5 = ?",
                         (a[0],)).fetchall()
         return [ a[0] ] + [ x[0] for x in b ]
@@ -496,7 +496,7 @@ class RepositoryManager(object):
         self.filter = [] if filter is None else filter
         self.search = [] if search is None else search
         self.timeout = timeout or 3
-        debug("Repostiory timeout setted to %ds" % self.timeout)
+        debug(u"Repostiory timeout setted to %ds" % self.timeout)
         if cache_path is None:
             self.cache_path = None
             debug("No repository cache")
@@ -510,14 +510,14 @@ class RepositoryManager(object):
                 os.mkdir(self.cache_path)
             # ensure directories are avaiblable
             if not os.access(self.cache_path, os.W_OK | os.X_OK):
-                raise Exception("%s is not writable or executable" % self.cache_path)
-            debug("Repository cache is in %s" % self.cache_path)
+                raise Exception(u"%s is not writable or executable" % self.cache_path)
+            debug(u"Repository cache is in %s" % self.cache_path)
 
     def __del__(self):
         # delete temporary files (used by db)
         for f in self.tempfiles:
             try:
-                debug("Removing temporary db file %s" % f)
+                debug(u"Removing temporary db file %s" % f)
                 os.unlink(f)
             except OSError:
                 pass
@@ -532,15 +532,15 @@ class RepositoryManager(object):
         '''
         Return a repostiory by its position in list
         '''
-        if type(key) == int:
+        if isinstance(key, int):
             return self.repos[key]
-        elif type(key) == str:
+        elif isinstance(key, basestring):
             for repo in self.repos:
                 if repo.config.name == key:
                     return repo
-            raise IndexError("No repository named: %s" % key)
+            raise IndexError(u"No repository named: %s" % key)
         else:
-            raise TypeError
+            raise TypeError(u"Invalid type %s for %" % (type(key), key))
 
     def __contains__(self, key):
         '''
@@ -561,21 +561,21 @@ class RepositoryManager(object):
         # check filter on name
         if len(self.filter) > 0:
             if config.name not in self.filter:
-                debug("Filtering repository %s" % config.name)
+                debug(u"Filtering repository %s" % config.name)
                 return
         # repository is offline
         if config.offline or offline:
-            debug("Registering offline repository %s (%s)" % (config.path, config.name))
+            debug(u"Registering offline repository %s (%s)" % (config.path, config.name))
             # we must force offline in cast of argument offline
             config.offline = True
             self.repos.append(Repository(config))
         # if path is local, no needs to create a cache
         elif istools.isfile(config.path):
-            debug("Registering direct repository %s (%s)" % (config.path, config.name))
+            debug(u"Registering direct repository %s (%s)" % (config.path, config.name))
             self.repos.append(Repository(config))
         # path is remote, we need to create a cache
         else:
-            debug("Registering cached repository %s (%s)" % (config.path, config.name))
+            debug(u"Registering cached repository %s (%s)" % (config.path, config.name))
             self.repos.append(self._cachify(config, temp, nosync))
 
     def _cachify(self, config, temp=False, nosync=False):
@@ -620,7 +620,7 @@ class RepositoryManager(object):
                 # if repo is out of date, download it
                 if rlast != llast:
                     try:
-                        arrow("Downloading %s" % original_dbpath)
+                        arrow(u"Downloading %s" % original_dbpath)
                         rdb.progressbar = True
                         ldb = open(config.dbpath, "wb")
                         rdb.consume(ldb)
@@ -637,7 +637,7 @@ class RepositoryManager(object):
                         raise
         except IOError as e:
             # if something append bad during caching, we mark repo as offline
-            debug("Unable to cache repository %s: %s" % (config.name, e))
+            debug(u"Unable to cache repository %s: %s" % (config.name, e))
             config.offline = True
         return Repository(config)
 
@@ -667,13 +667,13 @@ class RepositoryManager(object):
         Return a list of available images
         '''
         if len(self.onlines) == 0:
-            raise Exception("No online repository")
+            raise Exception(u"No online repository")
         ans = {}
         for pattern in patterns:
             path, image, version = Repository.split_image_path(pattern)
             # no image name, skip it
             if image is None:
-                warn("No image name in pattern %s, skipped" % pattern)
+                warn(u"No image name in pattern %s, skipped" % pattern)
                 continue
             # building image list
             images = {}
@@ -698,9 +698,9 @@ class RepositoryManager(object):
                         last = reduce(f, versions)
                         versions.remove(last)
                         for rmv in versions:
-                            del images["%s/%s:%s" % (repo, img, rmv)]
+                            del images[u"%s/%s:%s" % (repo, img, rmv)]
             # filter with pattern on path
-            filter_pattern = "%s/%s:%s" % (path, image, version)
+            filter_pattern = u"%s/%s:%s" % (path, image, version)
             for k in images.keys():
                 if not fnmatch.fnmatch(k, filter_pattern):
                     del images[k]
@@ -753,7 +753,7 @@ class RepositoryManager(object):
         Return a list of available payloads
         '''
         if len(self.onlines) == 0:
-            raise Exception("No online repository")
+            raise Exception(u"No online repository")
         # building payload list
         paylist = {}
         for reponame in self.onlines:
@@ -811,7 +811,7 @@ class RepositoryManager(object):
         Remove local cached repository files
         '''
         for reponame in self.select_repositories(patterns):
-            arrow("Purging cache of repository %s" % reponame)
+            arrow(u"Purging cache of repository %s" % reponame)
             db = os.path.join(self.cache_path, reponame)
             if os.path.lexists(db):
                 try:
@@ -858,11 +858,11 @@ class RepositoryManager(object):
                 sl = "#l##y#Local#R#  " if repo["local"] else "#l##c#Remote#R# "
                 rc = "#l##r#" if repo["offline"] else "#l##g#"
                 if o_state:
-                    ln +=  "%s%s " % (so, sl)
+                    ln +=  u"%s%s " % (so, sl)
                     rc = "#l##b#"
-                ln += "%s%s#R#"% (rc, name)
+                ln += u"%s%s#R#"% (rc, name)
                 if o_url:
-                    ln += "  (%s)" % repo["path"]
+                    ln += u"  (%s)" % repo["path"]
                 l.append(ln)
             s = os.linesep.join(l)
         out(s)
@@ -895,7 +895,7 @@ class RepositoryConfig(object):
     def __str__(self):
         l = []
         for k, v in self.items():
-            l.append("%s: %s" % (k, v))
+            l.append(u"%s: %s" % (k, v))
         return os.linesep.join(l)
 
     def __eq__(self, other):
@@ -1049,6 +1049,7 @@ class RepositoryConfig(object):
                 try:
                     setattr(self, k, kwargs[k])
                 except Exception as e:
-                    warn("Unable to set config parameter %s in repository %s: %s" % (k, self.name, e))
+                    warn(u"Unable to set config parameter %s in repository %s: %s" %
+                         (k, self.name, e))
             else:
-                debug("No such repository parameter: %s" % k)
+                debug(u"No such repository parameter: %s" % k)
diff --git a/installsystems/template.py b/installsystems/template.py
index 56e8025d8ad3d72a16b60848073055e0c753b21d..06ce72d22d63faa9d560f00e6492434cbbe4d4a3 100644
--- a/installsystems/template.py
+++ b/installsystems/template.py
@@ -39,7 +39,7 @@ from installsystems.printer import arrow
 class TargetAction(argparse.Action):
   def __call__(self, parser, namespace, values, option_string=None):
     if not os.path.isdir(values):
-      raise Exception("Invalid target directory %s" % values)
+      raise Exception(u"Invalid target directory %s" % values)
     namespace.target = values
 
 parser.add_argument("-n", "--hostname", dest="hostname", type=str, required=True)
@@ -57,7 +57,7 @@ setup = u"""# -*- python -*-
 
 from installsystems.printer import arrow
 
-arrow("hostname: %s" % namespace.hostname)
+arrow(u"hostname: %s" % namespace.hostname)
 
 # uncomment to extract payload named root in namespace.target directory
 #image.payload["rootfs"].extract(namespace.target)
diff --git a/installsystems/tools.py b/installsystems/tools.py
index c83aa84c37e015000cbc78c0a3783d640150f083..8898b008f0b01a5793a35005f02730a51eab3d41 100644
--- a/installsystems/tools.py
+++ b/installsystems/tools.py
@@ -189,8 +189,8 @@ class PipeFile(object):
     def close(self):
         if self.progressbar:
             self._progressbar.finish()
-        debug("MD5: %s" % self.md5)
-        debug("Size: %s" % self.consumed_size)
+        debug(u"MD5: %s" % self.md5)
+        debug(u"Size: %s" % self.consumed_size)
         self.fo.close()
 
     def read(self, size=None):
@@ -381,7 +381,7 @@ def human_size(num, unit='B'):
     if power >= len(prefixes):
         power = len(prefixes) - 1
     scaled = num / float(1024 ** power)
-    return "%3.1f%s%s" % (scaled, prefixes[power], unit)
+    return u"%3.1f%s%s" % (scaled, prefixes[power], unit)
 
 def time_rfc2822(timestamp):
     '''
@@ -409,16 +409,16 @@ def prepare_chroot(path, mount=True):
         mps = ("proc", "sys", "dev", "dev/pts", "dev/shm")
         arrow("Mouting filesystems")
         for mp in mps:
-            origin =  "/%s" % mp
+            origin =  u"/%s" % mp
             target = os.path.join(path, mp)
             if os.path.ismount(target):
-                warn("%s is already a mountpoint, skipped" % target)
+                warn(u"%s is already a mountpoint, skipped" % target)
             elif os.path.ismount(origin) and os.path.isdir(target):
-                arrow("%s -> %s" % (origin, target), 1)
+                arrow(u"%s -> %s" % (origin, target), 1)
                 try:
                     check_call(["mount",  "--bind", origin, target], close_fds=True)
                 except CalledProcessError as e:
-                    warn("Mount failed: %s.\n" % e)
+                    warn(u"Mount failed: %s.\n" % e)
     arrow("Tricks")
     exists = os.path.exists
     join = os.path.join
@@ -440,7 +440,7 @@ def prepare_chroot(path, mount=True):
                 open(resolv_trick_path, "wb")
             shutil.copy("/etc/resolv.conf", resolv_path)
     except Exception as e:
-        warn("resolv.conf tricks fail: %s" % e)
+        warn(u"resolv.conf tricks fail: %s" % e)
     # trick mtab
     try:
         mtab_path = join(path, "etc", "mtab")
@@ -452,7 +452,7 @@ def prepare_chroot(path, mount=True):
                 os.rename(mtab_path, mtab_backup_path)
             os.symlink("/proc/self/mounts", mtab_path)
     except Exception as e:
-        warn("mtab tricks fail: %s" % e)
+        warn(u"mtab tricks fail: %s" % e)
     # try to guest distro
     distro = guess_distro(path)
     # in case of debian disable policy
@@ -490,14 +490,14 @@ def unprepare_chroot(path, mount=True):
                 try:
                     os.unlink(mtab_trick_path)
                 except OSError:
-                    warn("Unable to remove %s" % mtab_trick_path)
+                    warn(u"Unable to remove %s" % mtab_trick_path)
             if exists(mtab_backup_path):
                 try: os.unlink(mtab_path)
                 except OSError: pass
                 try:
                     os.rename(mtab_backup_path, mtab_path)
                 except OSError:
-                    warn("Unable to restore %s" % mtab_backup_path)
+                    warn(u"Unable to restore %s" % mtab_backup_path)
 
         # untrick resolv.conf
         resolv_path = join(path, "etc", "resolv.conf")
@@ -512,14 +512,14 @@ def unprepare_chroot(path, mount=True):
                 try:
                     os.unlink(resolv_trick_path)
                 except OSError:
-                    warn("Unable to remove %s" % resolv_trick_path)
+                    warn(u"Unable to remove %s" % resolv_trick_path)
             if exists(resolv_backup_path):
                 try: os.unlink(resolv_path)
                 except OSError: pass
                 try:
                     os.rename(resolv_backup_path, resolv_path)
                 except OSError:
-                    warn("Unable to restore %s" % resolv_backup_path)
+                    warn(u"Unable to restore %s" % resolv_backup_path)
         # try to guest distro
         distro = guess_distro(path)
         # cleaning debian stuff
@@ -546,7 +546,7 @@ def chroot(path, shell="/bin/bash", mount=True):
     # prepare to chroot
     prepare_chroot(path, mount)
     # chrooting
-    arrow("Chrooting inside %s and running %s" % (path, shell))
+    arrow(u"Chrooting inside %s and running %s" % (path, shell))
     call(["chroot", path, shell], close_fds=True)
     # revert preparation of chroot
     unprepare_chroot(path, mount)
@@ -556,7 +556,7 @@ def is_version(version):
     Check if version is valid
     '''
     if re.match("^(\d+)(?:([-~+]).*)?$", version) is None:
-        raise TypeError("Invalid version format %s" % buf)
+        raise TypeError(u"Invalid version format %s" % buf)
 
 def compare_versions(v1, v2):
     '''
@@ -574,7 +574,7 @@ def compare_versions(v1, v2):
         elif isinstance(version, basestring):
             iv = re.match("^(\d+)(?:([-~+]).*)?$", version)
             if iv is None:
-                raise TypeError('Invalid version format: %s' % version)
+                raise TypeError(u"Invalid version format: %s" % version)
             rv = float(iv.group(1))
             if iv.group(2) == "~":
                 rv -= 0.1
@@ -582,7 +582,7 @@ def compare_versions(v1, v2):
                 rv += 0.1
             return rv
         else:
-            raise TypeError('Invalid version format: %s' % version)
+            raise TypeError(u"Invalid version format: %s" % version)
 
     fv1 = get_ver(v1)
     fv2 = get_ver(v2)
@@ -607,7 +607,7 @@ def get_compressor_path(name, compress=True, level=None):
     allcompressors = compressors if compress else decompressors
     # check compressor exists
     if name not in allcompressors.keys():
-        raise Exception("Invalid compressor name: %s" % name)
+        raise Exception(u"Invalid compressor name: %s" % name)
     # get valid compressors
     for compressor in allcompressors[name]:
         path = pathsearch(compressor[0])
@@ -616,7 +616,7 @@ def get_compressor_path(name, compress=True, level=None):
         if level is not None:
             compressor.append("-%d" % level)
         return compressor
-    raise Exception("No external decompressor for %s" % name)
+    raise Exception(u"No external decompressor for %s" % name)
 
 def render_templates(target, context, tpl_ext=".istpl", force=False, keep=False):
     '''
@@ -631,7 +631,7 @@ def render_templates(target, context, tpl_ext=".istpl", force=False, keep=False)
                 file_path = os.path.join(path[0], name)
                 arrow(tpl_path)
                 if os.path.exists(file_path) and not force:
-                    raise Exception("%s will be overwritten, cancel template "
+                    raise Exception(u"%s will be overwritten, cancel template "
                                     "generation (set force=True if you know "
                                     "what you do)" % file_path)
                 try:
@@ -640,7 +640,7 @@ def render_templates(target, context, tpl_ext=".istpl", force=False, keep=False)
                         with open(file_path, "w") as rendered_file:
                             rendered_file.write(template.render(context))
                 except Exception as e:
-                    raise Exception("Render template fail: %s" % e)
+                    raise Exception(u"Render template fail: %s" % e)
                 st = os.stat(tpl_path)
                 os.chown(file_path, st.st_uid, st.st_gid)
                 os.chmod(file_path, st.st_mode)