A catch-all mailbox is one that collects all the messages sent to inactive email addresses. For example, if your email address is email@example.com, but someone miswrites it and sends an email to firstname.lastname@example.org, it will still be received in the catch-all mailbox that you have set up. Only one mailbox per domain name can have this feature activated and in this way you’ll never miss messages because the other side has an out-of-date address or has made a mistake. The negative aspect of setting up a catch-all mailbox is that you may start receiving lots of unsolicited bulk email messages, but this issue can be fixed using anti-spam filtering software. It’s also essential to know that a mailbox with an enabled catch-all feature cannot redirect inbound emails to a 3rd-party mailbox.