System policies must have Full Control.

If you encounter event log errors like:
Application synchronization failed for Microsoft.Office.Excel.Server.ExcelServerSharedWebService.
Reason: System policies must have Full Control.
Then browse to Central Admin, Application Management, Policy for web application and uncheck the propertie 'operates as System account' for each account listed. See if that solves your problem.

If it is still happening:

with an event ID 6483 with error 'System policies must have full control'Resolved it by going to Central Administration --> Application Management --> Application Security --> Policy for Web Application, changed permissions for the Search user to Full Control

No more errors in the Event Viewer!

Still happening?

Take a look at the event viewer for your SQL Server machine and see which account is authenticating at the moment in which you are getting these errors. Then ensure that this account is infact listed in the System Policy. Don't forget to check EVERY Web application.


Hopes this helps get you going in the right direction!

Jason