When I attempt to demote a Domain Controller in Windows Server 2008 R2, I always get this message: "The Directory Service is missing mandatory configuration information, and is unable to determine the ownership of floating single master operation roles." Both of the Domain Controllers are on while I'm attempting the procedure, and are able to communicate (they are both virtual machines in VirtualBox). I have changed the master role a couple times, but it's currently assigned to the one I'm attempting to demote.

  • By the way, I did google it and most, if not all the answers I saw were related to domain controllers that were no longer on the network. Both of these still exist and are fully operational. – Davidw Mar 9 '13 at 4:33
  • And, it resolved itself! Apparently they just needed to communicate and replicate the domain information. – Davidw Mar 9 '13 at 5:02
  • This would have been moved to Server Fault since it's more about server/administration stuff, but since it sounds like it was just an issue with communication, I'll just leave it here for now since it resolved itself. For future reference, check out Server Fault for these sorts of questions. – nhinkle Mar 9 '13 at 6:35
  • Ok, thanks! I didn't realize there was a better place for this question. – Davidw Mar 9 '13 at 18:58