I have a SBS 2011 Essentials server which has recently started giving me problems. The server gets really slow and different functions on the server stop working like file sharing and print sharing. When I try to restart the server it can take 30+ minutes for it to completely shut down and start back up. After a restart the server runs fine for 6-12 hours then it start having the same problems.
I'm seeing a ton of Event ID 1206 (Active Directory Web Services was unable to determine if the computer is a global catalog server) errors in the Event Viewer. Once these errors start then I start see other DNS errors in the Event Viewer like - Event ID 4000 & 4015.