A catch-all feature that is enabled for a certain e-mailbox will allow you to receive email messages that are sent to addresses that do not actually exist. Otherwise said, if you disable an email address and somebody still sends an email to it, or to any misspelled address under the very same domain, you will receive the email in the catch-all mailbox. Using this functionality implies that you will no longer miss an email for any reason, which could be crucial in case you are running some company, for example. Since you may start receiving spam emails, you can combine the catch-all feature with anti-spam filtering software in order 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.