Continuous AppEvent Log Errors

We’re getting the following two errors every five minutes on our Domain Controller:

Source: SceCli EventID: 1202
User: NA
Security policies are propagated with warning. 0x5 : Access is denied.
Please look for more details in TroubleShooting section in Security Help.

Followed by:
Source:Userenv EventID: 1000
User: NT AUTHORITY\SYSTEM
The Group Policy client-side extension Security was passed flags (17) and returned a failure status code of (5).

The Microsoft Knowledge Base said to be sure the Group Policy was applied and it is, the Default Policy in fact. The only other Group Policy that’s applied is to the OU that contains our Terminal Server.

Suggestions anyone?