I started to deploy the 10.2 agent on one of my computer lab and I get these strange errors:

Full Message:An unknown error occurred while applying policy Windows Default Policy (EL).
Additional Information:None
Date:June 3, 2009 3:37:15 PM
Acknowledged Date:None
Message ID:POLICYHANDLERS.CommonClasses.UnknownApplyPolici esError
Probable Cause URL:None
Log ID:8b519fc765e9c0df286dcf40a2c40dec
Related Objects:/Policies/Windows Default Policy (EL)

What could cause this error ? The windows group policy seems to be applied and to work correctly. The eventvwr is full of group policy errors.