We are running a mixed Exchange 2003/2007 environment (both SP2). We have mailboxes on both platforms.
The Exchange 2003 RUS server is due to be decommed. I believe before we can uninstall Exchange from it, we need to move the RUS role to another server? But we can't move it to a 2007 box can we, because 2007 doesn't use RUS? So how do we get rid of it?