A catch-all email mailbox receives emails sent to inactive email addresses under the same domain name. For instance, an email sent to the miswritten email@example.com will be delivered to firstname.lastname@example.org if the catch-all feature has been enabled for the latter. Thus, you can receive emails from acquaintances or customers who may have sent a message to your email address with a spelling mistake or to an obsolete 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 activated for such a mailbox. This is so because of 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 re-sent to a 3rd-party mailbox.