diff --git a/couchpotato/core/helpers/encoding.py b/couchpotato/core/helpers/encoding.py
index bcc698d..9f361a1 100644
--- a/couchpotato/core/helpers/encoding.py
+++ b/couchpotato/core/helpers/encoding.py
@@ -60,9 +60,14 @@ def sp(path, *args):
 
     path = os.path.normcase(os.path.normpath(ss(path, *args)))
 
+    # Remove any trailing path separators
     if path != os.path.sep:
         path = path.rstrip(os.path.sep)
 
+    # Add a trailing separator in case it is a root folder on windows
+    if len(path) == 2 and path[1] == ':':
+        path = path + os.path.sep
+
     return path
 
 def ek(original, *args):
diff --git a/couchpotato/core/helpers/variable.py b/couchpotato/core/helpers/variable.py
index 1cf1f48..0b1ca9d 100644
--- a/couchpotato/core/helpers/variable.py
+++ b/couchpotato/core/helpers/variable.py
@@ -2,7 +2,7 @@ from couchpotato.core.helpers.encoding import simplifyString, toSafeString, ss
 from couchpotato.core.logger import CPLog
 import collections
 import hashlib
-import os.path
+import os
 import platform
 import random
 import re
@@ -219,3 +219,7 @@ def splitString(str, split_on = ',', clean = True):
 
 def dictIsSubset(a, b):
     return all([k in b and b[k] == v for k, v in a.items()])
+
+def isSubFolder(sub_folder, base_folder):
+    # Returns True is sub_folder is the same as or in base_folder
+    return base_folder.rstrip(os.path.sep) + os.path.sep in sub_folder.rstrip(os.path.sep) + os.path.sep
diff --git a/couchpotato/core/plugins/renamer/main.py b/couchpotato/core/plugins/renamer/main.py
index 2c6df8a..b53dfe8 100755
--- a/couchpotato/core/plugins/renamer/main.py
+++ b/couchpotato/core/plugins/renamer/main.py
@@ -3,7 +3,7 @@ from couchpotato.api import addApiView
 from couchpotato.core.event import addEvent, fireEvent, fireEventAsync
 from couchpotato.core.helpers.encoding import toUnicode, ss, sp
 from couchpotato.core.helpers.variable import getExt, mergeDicts, getTitle, \
-    getImdb, link, symlink, tryInt, splitString, fnEscape
+    getImdb, link, symlink, tryInt, splitString, fnEscape, isSubFolder
 from couchpotato.core.logger import CPLog
 from couchpotato.core.plugins.base import Plugin
 from couchpotato.core.settings.model import Library, File, Profile, Release, \
@@ -125,7 +125,7 @@ class Renamer(Plugin):
             return
         else:
             for item in no_process:
-                if '%s%s' % (base_folder, os.path.sep) in item:
+                if isSubFolder(item, base_folder):
                     log.error('To protect your data, the media libraries can\'t be inside of or the same as the "from" folder.')
                     return
 
@@ -157,7 +157,7 @@ class Renamer(Plugin):
 
         if media_folder:
             for item in no_process:
-                if '%s%s' % (media_folder, os.path.sep) in item:
+                if isSubFolder(item, media_folder):
                     log.error('To protect your data, the media libraries can\'t be inside of or the same as the provided media folder.')
                     return
 
@@ -508,7 +508,10 @@ class Renamer(Plugin):
                         os.remove(src)
 
                         parent_dir = os.path.dirname(src)
-                        if delete_folders.count(parent_dir) == 0 and os.path.isdir(parent_dir) and not '%s%s' % (parent_dir, os.path.sep) in [destination, media_folder] and not '%s%s' % (base_folder, os.path.sep) in parent_dir:
+                        if delete_folders.count(parent_dir) == 0 and os.path.isdir(parent_dir) and \
+                            not isSubFolder(destination, parent_dir) and not isSubFolder(media_folder, parent_dir) and \
+                            not isSubFolder(parent_dir, base_folder):
+
                             delete_folders.append(parent_dir)
 
                 except:
@@ -1044,7 +1047,7 @@ Remove it if you want it to be renamed (again, or at least let it try again)
         return release_download['id'] and release_download['downloader'] and release_download['folder']
 
     def movieInFromFolder(self, media_folder):
-        return media_folder and '%s%s' % (sp(self.conf('from')), os.path.sep) in sp(media_folder) or not media_folder
+        return media_folder and isSubFolder(media_folder, sp(self.conf('from'))) or not media_folder
 
     def extractFiles(self, folder = None, media_folder = None, files = None, cleanup = False):
         if not files: files = []