We're running Exchange 2010 on a Windows 2000 functional level domain (with 2003 DCs) and we're getting ready to upgrade our domain to 2008 R2. Rather than upgrade the existing domain (with all of it's orphaned accounts and bad data) we have decided to create a new domain from scratch and gradually migrate over to it using domain trusts as a stop gap.
The email address domain isn't changing... @somecompany.com, but the realm is going from abc.def.ghi.net to ijk.local.
Moving users and computers to the new domain is easy, it's getting them access to their respective exchange accounts during the migration and the eventual final move of exchange from the old to new domain that has me stumped. Anyone done something like this before?