Security Policy 1001
We had an annoying warning showing every 5 minutes on our Read Only Domain Controllers. This didn't affect service but meant we were losing our logs of important events (should the have occurred) "Security policy cannot be propagated. Security Configuration Server (in services.exe) is not ready. This is probably in system reboot. Policy will be tried again in the next propagation." Source: SceCli Event: ID 101 We tracked this down to a GPO which was populating the local Administrators group. Obviously a Domain Controller has no local users or groups so this was causing the issue. Ensuring that the GPO did not apply to the Domain Controllers - yes the GPO was linked at the root! fixed the issue. It is strange that we did not see the warnings on our main Domain Controllers only on the Read Only DC's as this would have affected all DCs the same (I would have thought)