After demoting one of your Domain Controllers you might be faced with the following error when using the Exchange 2010 Management Console.
An error caused a change in the current set of domain controllers
This error might appear at different places in you Exchange 2010 Management Console and under different error messages that all have the sentence above in common. However using the Exchange Management Shell works flawlessly.
As weird as it might sound manually specifying a Domain Controller for the Exchange Server to use did not solve the problem, however during my troubleshooting I tried to log on as another user and the error was miraculously gone.
This led me to believe the problem was indeed from the user profile rather than from exchange itself. Further investigation showed the culprit as the “Exchange Management Console” file located in the “C:\Users\%username%\AppData\Roaming\Microsoft\MMC\” directory.
Simply browsing to “C:\Users\%username%\AppData\Roaming\Microsoft\MMC\” and deleting the “Exchange Management Console” solved the problem.