A catch-all functionality that is activated for a particular mailbox will allow you to receive email messages that are sent to email addresses that do not actually exist. Otherwise put, if you deactivate an email address and someone still sends a message to it, or to any miswritten email address under the same domain, you’ll get the message in the catch-all mailbox. Using this feature implies that you won’t miss an email for any reason, which could be crucial in case you are running a company, for example. Since you may begin receiving junk messages, you can use the catch-all option with anti-spam filters so as to receive only legitimate email messages in your inbox. Only one mailbox per domain name can be a catch-all one and email forwarding cannot be set up for a catch-all mailbox.