A catch-all feature that is activated for a specific mailbox will permit you to receive email messages that are sent to addresses that do not really exist. To put it differently, if you disable an email address and someone still sends an email message to it, or to any mistyped address under the same domain, you will receive the message in the catch-all mailbox. Using this feature implies that you will no longer miss an email for any reason whatsoever, which could be essential if you run a company, for instance. Since you may begin receiving spam email messages, you can use the catch-all functionality with anti-spam filtering software so as to receive only real emails in your inbox. Only one single mailbox per domain can be a catch-all one and email forwarding cannot be activated for a catch-all mailbox.