A catch-all functionality that is enabled for a certain e-mailbox will allow you to receive emails that are sent to email addresses that do not really exist. To put it differently, if you disable an email address and somebody still sends a message to it, or to any misspelled email address under the exact same domain, you’ll get the message in the catch-all mailbox. Using this functionality means that you will no longer miss an email for any reason whatsoever, which could be crucial in case you run some business, for instance. Since you may begin receiving unsolicited emails, you can combine the catch-all option with email filters in order to get only legitimate email messages 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.