Current setup is 3 exchange 2010 servers. One of these servers in a DC (exch3) and I'd like to correct that problem as there is finally another 2008 DC available in the site. There are no current active DBs on exch3; it is just used to hold copies. I want to keep exchange on the server but remove AD. All FSMO roles have been transferred to the new DC and there is a GC available. Is it as simple as DCPromo'ing it down? Thanks

Not supported, 1st remove exch then dcpromo, then dcpromo again and put ad back on.Sukh

No, you cannot run DCPROMO on an Exchange server: http://technet.microsoft.com/en-us/library/aa996719.aspx You'd have to uninstall Exchange first - unfortunately.Please mark as helpful if you find my contribution useful or as an answer if it does answer your question. That will encourage me - and others - to take time out to help you.

Thanks to both of you. I was really hoping that wasn't the case...