http://blogs.msdn.com/psssql/archive/2009/07/01/when-in-doubt-reboot.aspxI tend to get quite a bit of Kerberos related cases.  These are related across the box, from the Engine, to Reporting Services to just straight connectivity with custom applications.  I had one given to me yesterday because the engineer hadenCommunityServer 2.1 SP1 (Build: 61025.2)