I have setup a catch-all mailbox (email@example.com). If i send a mail to firstname.lastname@example.org, this should ideally be routed to email@example.com. The problem is, that it only works from domains sending mail on the same server.
If i send a mail to firstname.lastname@example.org from a domain sitting on another server, it returns an error "Unknown user"
Please can someone advise if I am doing something wrong, or is this a common problem.