The last two times I've installed Windows Updates (security patches only) on our W2K03 file/print server, upon reboot, it has resulted in the OS crashing at the point where during logon the status banner reads 'applying computer settings'. This will result in an endless loop as it then reboots again, and the same thing happens.
Both times, the only fix has been to remove the recently installed updates through Safe Mode. Event Viewer did not reveal anything instructive. We're planning on replacing this server next year, so my plan is to simply not install any further updates. I would prefer to determine the problem, of course but I'm not sure where to go from here.
