Now that we migrated all user accounts from an old server (mail.domain.com) to the new server (mail1.domain.com). We set a CN name to point mail1.domain.com to mail.domain.com so that users don't have to change the settings in MS Outlook. We are able to send emails internally but not beyond our domain. We receive an error like this: 554 5.7.1 <firstname.lastname@example.org>: Relay access denied.
I've set the Global - MTA - external and internal to the same relay server but that doesn't help. Any suggestions?