A catch-all functionality that is activated for a particular mailbox will permit you to receive email messages that are sent to email addresses that do not actually exist. Otherwise stated, if you disable an email address and someone still sends an email to it, or to any mistyped address under the very same domain name, you’ll get the message in the catch-all mailbox. Using this functionality implies that you will no longer miss an email for any reason whatsoever, which could be vital if you run a business, for instance. Since you may start receiving unsolicited messages, you can combine the catch-all functionality with anti-spam filtering software so as to receive only real emails in your inbox. Only one mailbox per domain can be a catch-all one and email forwarding cannot be set up for a catch-all mailbox.