This server is a terminal services server. I made 2 changes to this server: 1) updated the registry on this server to point to a new terminal licensing server and 2) changed the drive letter on the hard drive with the data (physically separate from the hard drive with the OS). I then rebooted. After rebooting I see the error message "At least one service failed....check Event Viewer..). I checked Event Viewer and found I couldn't open any of the messages. I then checked services and found that very few services had actually started, including: Server, NetLogon, and many others that were supposed to start automatically. When I tried to manually start them I got either "access denied" errors or more frequently " the dependencies service or group failed to start". I'm thinking I'll probably just have to reinstall the OS, which isn't a huge deal, but I'd sure like to know why it quit working when the changes I made were (I thought) fairly minor. I even went back and took out the change I made to the registry. I can't imagine changing the drive letter would make a difference but I can't change it back anyway because Disk Management won't open.