--- C:\Python27\Lib\mimetypes.py	Wed Jun 27 11:20:26 2012
+++ C:\Python27\Lib\mimetypes_fixed.py	Wed Jun 27 11:33:11 2012
@@ -254,23 +254,23 @@
                 i += 1
 
         default_encoding = sys.getdefaultencoding()
-        with _winreg.OpenKey(_winreg.HKEY_CLASSES_ROOT,
-                             r'MIME\Database\Content Type') as mimedb:
-            for ctype in enum_types(mimedb):
+        with _winreg.OpenKey(_winreg.HKEY_CLASSES_ROOT, '') as hkcr:
+            for subkeyname in enum_types(hkcr):   # enum_types() sub remains unchanged
                 try:
-                    with _winreg.OpenKey(mimedb, ctype) as key:
-                        suffix, datatype = _winreg.QueryValueEx(key,
-                                                                'Extension')
+                    with _winreg.OpenKey(hkcr, subkeyname) as subkey:
+                        if subkeyname[0] == ".":    # Only check entries that begin with dots, i.e. file extensions
+                            # subkeyname is the file extension
+                            mimetype, datatype = _winreg.QueryValueEx(subkey, 'Content Type')  # throws EnvironmentError if no 'Content Type' value
+                            if datatype != _winreg.REG_SZ:
+                                continue
+                            try:
+                                subkeyname = subkeyname.encode(default_encoding) # omit in 3.x!
+                            except UnicodeEncodeError:
+                                continue
+                            self.add_type(mimetype, subkeyname, strict)
+                            
                 except EnvironmentError:
                     continue
-                if datatype != _winreg.REG_SZ:
-                    continue
-                try:
-                    suffix = suffix.encode(default_encoding) # omit in 3.x!
-                except UnicodeEncodeError:
-                    continue
-                self.add_type(ctype, suffix, strict)
-
 
 def guess_type(url, strict=True):
     """Guess the type of a file based on its URL.