A catch-all mailbox receives email messages sent to inactive addresses under the same domain name. For instance, a message sent to the misspelled firstname.lastname@example.org will be delivered to email@example.com if the catch-all feature has been enabled for the latter. Thus, you can receive messages from friends or clients who may have sent a message to your email address with a typographical error or to an out-of-date one, which they may still have, but you have already deactivated. Just one single mailbox per domain can be a catch-all one and email forwarding cannot be enabled for such a mailbox. This is due to the fact that at some point you may begin receiving spam emails in the catch-all mailbox and the forwarding limitation implies that the spam will not be redirected to a 3rd-party mailbox.