A catch-all mailbox is one that collects all the email messages sent to inactive addresses. For instance, if your email address is email@example.com, but somebody mistypes it and sends a message to firstname.lastname@example.org, it will still be received in the catch-all mailbox that you have configured. Just one mailbox per domain name can have this feature activated and in this way you’ll never miss emails because the other side has an outdated address or has made a mistake. The disadvantage of having a catch-all mailbox is that you may begin receiving lots of junk messages, but this issue can be fixed using anti-spam filtering software. It’s also important to remember that a mailbox with an activated catch-all functionality cannot redirect incoming email messages to a third-party email address.