We have Exchange deployed in a resource forest. Our accounts forest is still Windows 2000 AD only - no Windows 2003 domain controllers - beyond my control. When I migrate mailboxes from Exchange 2000/2003 to Exchange 2007 the link to the Windows 2000 account stays in place and works. Problem: Creating new linked mailboxes. Since there are no 2003 domain controllers in the accounts forest, Exchange 2007 won't let me create a mailbox linked back to the accounts forest because it won't talk to domain controllers before 2003 SP1. Is there any way around this?