I am currently running a Windows Server 2003 machine with AD, Exchange, and web setup. As of about 2 weeks ago, out of the blue, the machine decided that it will no longer connect to either exchange or AD - when I try to connect, I receive an error saying that the server is not operational. What could this be??? The server is a domain controller within a forest, but has never had trouble connecting TO ITSELF. I have checked for viruses over and over again and find nothing. I have also installed DNS Server on the machine since some recommended that it might be the cause of the problem, but that did not help. If anyone has any ideas, please let me know.