A catch-all email mailbox receives email messages sent to inactive email addresses under the same domain. For instance, an email sent to the mistyped email@example.com will be delivered to firstname.lastname@example.org in case the catch-all feature has been enabled for the latter. In this way, you can get messages from colleagues or clients who may have sent a message to your email address with a spelling error or to an out-of-date one, which they may still have, but you have already deactivated. Only one single mailbox per domain name can be a catch-all one and email forwarding cannot be set up for such a mailbox. This is due to the fact that at some moment you may begin receiving spam messages in the catch-all mailbox and the forwarding limitation means that the spam will not be delivered to a third-party mailbox.