A catch-all mailbox receives emails sent to non-existent email addresses under the same domain name. For example, a message sent to the miswritten [email protected] will be delivered to [email protected] if the catch-all feature has been enabled for the latter. In this way, you can receive emails from acquaintances or clients who may have sent a message to your email address with a typo 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 set up for such a mailbox. The latter is due to the fact that at a certain point you may begin receiving spam emails in the catch-all mailbox and the forwarding restriction means that the spam will not be received in a 3rd-party mailbox.