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emails from friends or customers who may have sent a message to your email address with a typographical error or to an out-of-date one, which they may still have, but you have already disabled.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