Windows user profile issues
If the user profile on the client machine is corrupt, the logon script (and Windows GPO settings) cannot run. This problem can be resolved by recreating the user profile.
When you recreate a user profile, the user’s existing My Documents folder, Favorites, and other custom data and settings are not automatically transferred to the new profile. Do not delete the existing, corrupted profile until you have verified that the new profile has solved the problem and copied the user’s existing data to the new profile.