If your Application event log contains:
Event ID: 1000
Event Source: Userenv
Description: Windows cannot read the history of GPOs from the registry
you have some missing or corrupt registry entries. This causes Group Policy to NOT be applied on your computer.
To fix this problem:
1. Use Regedt32.exe to navigate to:
2. On the Security / Permissions menu, make sure that the History key and sub-keys have the following permissions:
|Administrators||Read, Full Control|
|System||Read, Full Control|
3. Delete all the sub-keys of the History key. DO NOT delete the History key.
5. Check the Application event log for Event ID 1704.
NOTE: the History sub-keys are re-created.