On a Server 2008 R2 machine, I had an issue demoting from being a Domain Controller, after moving the FSMO roles onto a new machine. This was after a second domain controller died. I am not sure of the previous history of where the FSMO roles were for this client.
Two new DC’s were created and promoted, after cleaning up DNS to remove the old configuration of the dead DC.
The Error
I was provided with the following error in a dialog box and in the event log