If your server's event log issues the following every 5 minutes:
Event Type: Error Event Source: Userenv Event Category: None Event ID: 1000 Description: The Group Policy client-side extension Security was passed flags (17) and returned a failure status code of (1208). Event Type: Warning Event Source: SceCli Event Category: None Event ID: 1202 Description: Security policies are propagated with warning. 0x4b8 : An extended error has occurred. Please look for more details in TroubleShooting section in Security Help.and the Winlogon.log files contains:
Error 1332: No mapping between account names and security IDs was done. Cannot find Power Users.
you have references to the Power Users group in the Local Security settings.
Remove all references to Power Users:
1. Control Panel / Administrative Tools / Local Security Policy.
2. Select Local Policies / User Rights Assignment.
3. Double-click each item under User Rights Assignments and clear the Power Users check box. Press OK.
4. Restart your server.
5. Inspect the Winlogon.log file and Event Viewer to make sure that the problem is solved.
NOTE: Power Users is NOT a built-in local group on a server.