A catch-all email mailbox receives emails sent to nonexistent email addresses under the exact same domain name. For instance, an email sent to the mistyped 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 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 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 point you may begin receiving spam email messages in the catch-all mailbox and the forwarding limitation implies that the spam will not be redirected to a third-party mailbox.