A catch-all email mailbox is one that gathers all the messages sent to inactive addresses. For instance, if your address is email@example.com, but someone miswrites it and sends a 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mailbox per domain can have this feature activated and thus you’ll never miss messages because the other party has an out-of-date email address or has made a mistake. The negative aspect of setting up a catch-all mailbox is that you may start receiving lots of junk messages, but this issue can be rectified by using an anti-spam protection solution. It’s also essential to keep in mind that a mailbox with an activated catch-all feature cannot redirect incoming messages to a third-party address.