Out Exchange 2007 servers changed GC and DC to a GC/DC in another site (same domain). Why would it do that?Ray

Hey Ray,That could be because of number of reasons. If you can see the event ID 2080 and 2081 with source MSExchangeDSAccess then you can understand the reason why it changed to another domain controller. Take a look at http://support.microsoft.com/default.aspx/kb/316300However to troubleshoot this you can check the health of domain controllers in that site. Like replication, availability, rechability etc. The above linked article will give you an overview of what to check.Milind Naphade | MCTS:M | http://www.msexchangegeek.com

Hi Ray,I agree with Milind. I suggest you run Exbpa to do a health check and see if it can find some clues. Please read KB316300, The KB is for Exchange 2000 and 2003, in Exchange 2007, we don't need to increase the diagnostics logging level and we could check the result directly. Please paste the event 2080 here for our discussion. Please describe your Exchange topology in detail and let us know what have you done before the change happen.Thanks,Elvis

Agree with all the posts..Info..If the Exchange IP belongs to that site, there is a possibility it registers with the domain controller of that site.

As it turned out, my default domain controller group policy was corrupt (somehow, go figure). Anyway, I fixed it, added the Exchange Servers and Exchange Enterprise Servers (mixed 2003/2007 environment) back to the GPO for managing auditing and security log. Once that replicated all was well.

Cool. Thank you for sharing with us. :)