Just a heads up. I had a DC where I installed Eset NOD32BE 3.0 with Remote server. This pretty much brought down a Windows 2003 domain controller. None of the client PCs were talking to it. There screens would be stuck at "Apply Settings". I solved it by stopping the PowerChute Network Shutdown service and that immediately fixed the issue. I unstalled Powerchute v6, installed the new APC Powerchute 7 version and that worked fine as well. I do not understand how all of a sudden, installing NOD32, triggered Powerchute to cause havoc on the DC.