A catch-all feature that is enabled for a particular mailbox will allow you to receive emails that are sent to addresses that do not really exist. Otherwise put, if you disable an email address and somebody still sends an email to it, or to any mistyped email address under the very same domain name, you will get the email in the catch-all mailbox. Using this feature means that you will no longer miss an email for any reason, which could be vital if you run some company, for instance. Since you may begin receiving junk email messages, you can use the catch-all option with anti-spam filtering software in order to receive only authentic emails in your inbox. Only one single mailbox per domain can be a catch-all one and email forwarding cannot be enabled for a catch-all mailbox.