Just swapped in a new SBS 2008 server today. Did not perform a migration this time (old server was a mess), but chose a completely new domain and migrated everything over manually. Went well, only snag is that replies to email@example.com bounce back with a non-deliverable bounce, even though I added olddomain.local to the Accepted Domains and double-checked that each user has an @olddomain.local SMTP address.
I right-clicked/opened properties on one of the old internal users in the To: field auto-complete (stored in the .N2K Nickname file) and it appears that the olddomain.local entries don't have an SMTP address.
Thankfully there wasn't a lot of users so we just deleted the auto-complete entries, typed their names and hit Check Names to repopulate it with ones that work, but anyone who replies to an old email that was sent from an internal user will bounce.
Is there a nice way to do this?
I should add that this is not the first (or second) time this has happened: in all cases where a swing or a Microsoft documented method to migrate the existing AD, etc. over to a new SBS 2008 server has not been performed, we've had issues with emailing to olddomain.local accounts.