A catch-all mailbox receives emails sent to inactive addresses under the very same domain. For instance, a message sent to the miswritten suport@domain.com will go to support@domain.com if the catch-all feature has been activated for the latter. In this way, you can receive email messages from mates or clients who may have sent a message to your email address with a typographical error or to an obsolete one, which they may still have, but you have already disabled. Only one mailbox per domain name can be a catch-all one and email forwarding cannot be activated for such a mailbox. The latter is due to the fact that at some point you may start receiving spam emails in the catch-all mailbox and the forwarding limitation implies that the spam will not be re-sent to a 3rd-party mailbox.
