A catch-all email mailbox receives email messages sent to nonexistent email addresses under the exact same domain name. For instance, an email sent to the mistyped firstname.lastname@example.org will go to email@example.com in case the catch-all feature has been activated for the latter. In this way, you can receive email messages from acquaintances or customers who may have sent a message to your email address with a spelling error or to an old one, which they may still have, but you have already deleted. Only one single mailbox per domain can be a catch-all one and email forwarding cannot be enabled for such a mailbox. The latter is due to the fact that at a certain moment you may begin receiving spam emails in the catch-all mailbox and the forwarding restriction means that the spam will not be sent to a third-party mailbox.