How can I switch my primary and secondary Internet domains?

I have registered two Internet domains in my company -- abc.com and def.com. I created a global domain record -- abc.com as the primary and def.com as the secondary. Users receive mail through both addresses user@abc.com and user@def.com.

But when I change the order to make def.com the primary and abc.com the secondary, user@def.com's email is being blocked. The error says "unable to relay mail." Def.com is not an external domain.

I need to migrate all users to user@def.com and secondary as user@abc.com.
It sounds like some of your relay fields are not set up completely. Check your server configuration document. Wherever you see abc.com in relay fields, you should add def.com.

This was first published in June 2003