I am trying to prepare for some serve upgrades in a month or so. Currently I am running exchange server 2010 on a Windows 2003 R2 server. When exchange was initially installed the computer was a Domain controller. I am looking at upgrading a couple servers to Windows 2008 R2. Because I wanted to upgrade Active Directory to 2008. I was thinking of moving the Domain Controller off the Exchange server. Before I upgrade the system I have 4 other Domain Controllers, Running windows 2003. How do make my exchange server a member server?