--- a/mailnews/local/src/nsMsgMaildirStore.cpp
+++ b/mailnews/local/src/nsMsgMaildirStore.cpp
@@ -198,16 +198,20 @@ NS_IMETHODIMP nsMsgMaildirStore::CreateF
   rv = CreateDirectoryForFolder(path, isServer);
   NS_ENSURE_SUCCESS(rv, rv);
 
   // Make sure the new folder name is valid
   nsAutoString safeFolderName(aFolderName);
   NS_MsgHashIfNecessary(safeFolderName);
 
   path->Append(safeFolderName);
+  bool exists;
+  path->Exists(&exists);
+  if (exists) //check this because localized names are different from disk names
+    return NS_MSG_FOLDER_EXISTS;
 
   rv = CreateMaildir(path);
   NS_ENSURE_SUCCESS(rv, rv);
 
   nsCOMPtr<nsIMsgFolder> child;
   // GetFlags and SetFlags in AddSubfolder will fail because we have no db at
   // this point but mFlags is set.
   rv = aParent->AddSubfolder(safeFolderName, getter_AddRefs(child));