A catch-all mailbox is one that gathers all the email messages sent to non-existent email addresses. For example, if your address is firstname.lastname@example.org, but somebody miswrites it and sends an email to email@example.com, it will still be received in the catch-all mailbox that you have created. Only one single mailbox per domain can have this feature activated and in this way you’ll never miss messages because the other side has an out-of-date email address or has made a spelling mistake. The negative aspect of creating a catch-all mailbox is that you may begin receiving plenty of unsolicited emails, but this issue can be resolved using anti-spam protection software. It’s also essential to keep in mind that a mailbox with an enabled catch-all feature cannot redirect incoming messages to a 3rd-party address.