A catch-all email mailbox is one that gathers all the messages sent to inactive addresses. For example, if your email address is email@example.com, but someone miswrites it and sends an email message to firstname.lastname@example.org, it will still be received in the catch-all mailbox that you have set up. Just one single mailbox per domain name can have this feature activated and thus you’ll never miss messages because the other side has an out-of-date address or has made a typographical error. The negative aspect of using a catch-all mailbox is that you may begin receiving plenty of spam emails, but this issue can be rectified using anti-spam protection software. It is also important to know that a mailbox with an enabled catch-all functionality cannot forward inbound messages to a third-party email address.