Cannot log off Windows 2000 Server

Logged on as Administrator to Win2K SP3 Server. This is a Small Business server installation. A few days ago we started to see that we cannot log off the server. Nor can we shut it down or use restart. Go to the Start button, choose Shutdown and select any option from the drop down menu, the dialog goes away after you hit ok and nothing happens. This will occur on Terminal server sessions and on the console.

Eventually we found that if we use Task Manager to “End Process” all the instances of DirectX logoff functionality is restored. Ok, so we upgraded to the recommended new version 9.0a of DirectX and it has NOT solved the problem.

Any insight appreciated!