I have upgraded all my DC's to Windows 2003 SP2(some of them are on R2). My existing domain level is Windows 2000 Native mode & I have Exchange 2000 which is running under Exchange 2000 Native mode. I am in preparation of moving to Exchange 2007. I would like to raise the domain & forest functional levels from Windows 2000 Native mode to Windows 2003 mode before installing the first Exchange 2007. Can I just proceed or do I need to do some adprep, domainprep, forestprep, etc.
What is the best recommendated approach for me. Deploy Exchange 2007 and move all the mailboxes and then upgrade domain & forest funtional levels. Or first move to Windows 2003 mode and then proceed with Exchange 2007?