diff --git a/image_creator/os_type/unix.py b/image_creator/os_type/unix.py
index 4a465991d194f1b1c7f591fead759fffc612b8aa..4999f7dd72523920f6eb4858d1f9dec1f6d35277 100644
--- a/image_creator/os_type/unix.py
+++ b/image_creator/os_type/unix.py
@@ -15,7 +15,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-"""This module hosts OS-specific code common to all Unix-like OSs."""
+"""This module hosts OS-specific code common to all Unix-like OSes."""
 
 from image_creator.os_type import OSBase, sysprep, add_sysprep_param
 
diff --git a/image_creator/os_type/unsupported.py b/image_creator/os_type/unsupported.py
index 6b8d9cba54ae306096f61ba267b6b19e3aed20d2..41ef24eff69ba72870b877d5c36220b901d05bb9 100644
--- a/image_creator/os_type/unsupported.py
+++ b/image_creator/os_type/unsupported.py
@@ -15,13 +15,13 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-"""This module hosts code to handle unknown OSs."""
+"""This module hosts code to handle unknown OSes."""
 
 from image_creator.os_type import OSBase
 
 
 class Unsupported(OSBase):
-    """OS class for unsupported OSs"""
+    """OS class for unsupported OSes"""
     def __init__(self, image, **kwargs):
         super(Unsupported, self).__init__(image, **kwargs)
 
@@ -31,7 +31,7 @@ class Unsupported(OSBase):
 
     def _do_mount(self, readonly):
         """Mount partitions in correct order"""
-        self._mount_error = "not supported on this media"
+        self._mount_error = "not supported for this media"
         return False
 
 # vim: set sta sts=4 shiftwidth=4 sw=4 et ai :
diff --git a/image_creator/os_type/windows/__init__.py b/image_creator/os_type/windows/__init__.py
index 388d88aeb18db41bd3efa95a5ec46e0ed71aa502..fccbd2d73092367e11506b62d744f49eb644176e 100644
--- a/image_creator/os_type/windows/__init__.py
+++ b/image_creator/os_type/windows/__init__.py
@@ -16,7 +16,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """This package hosts OS-specific code common for the various Microsoft
-Windows OSs."""
+Windows OSes."""
 
 from image_creator.os_type import OSBase, sysprep, add_sysprep_param
 from image_creator.util import FatalError