I need to change everyone's UserPrincipalName (UPN) in our AD domain. The only thing that is changing is the domain name, e.g:
Current UPN: andy.chips@domain.local
New UPN: andy.chips@domain.com
If I change the UPN in AD it will wipe out all the existing users with the @domain.local suffix on the next User Directory sync. How do I prevent that and get the User Directory sync to pull in the new UPN whilst keeping the users' existing groups, etc?
I toyed around with changing the User Schema settings in User Directories and tried things like sAMAccountName"domain.com" to force the new domain, but that doesn't work, and to be honest, I'm only guessing at the syntax (assuming there's a valid one).
Alternatively, I assume I'd have to get involved in some hideous SQL queries, and I have no idea where to start with that one.
Advice please.
Andy.