After a reboot the windows time reset itself to 26 March 2007. This meant it could not connect to any other servers in the domain. We have set the time to the correct value but we are having intermittent NetBios name problems. I want to understand whether the clock resetting is a red herring or a clue to the problem.
We had a similar problem that occurred whenever windows updates would run and sit for a while before the required reboot. The clock would always reset to midnight. It drove me nuts, and always killed our database replication.
The only solution we were able to find was to disable automatic updates. Now we manually run updates and reboot immediately. (And are in the process of moving the content to a new virtual Windows 2008 Server).