A catch-all mailbox receives emails sent to invalid email addresses under the very same domain. For example, a message sent to the mistyped suport@domain.com will be delivered to support@domain.com in case the catch-all feature has been activated for the latter. Thus, you can receive messages from mates or clients who may have sent a message to your email address with a typographical error or to an outdated one, which they may still have, but you have already deleted. Just 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 a certain point you may start receiving spam emails in the catch-all mailbox and the forwarding limitation implies that the spam will not be received in a third-party mailbox.