A catch-all email mailbox is one that gathers all the messages sent to non-existent email addresses. For instance, if your address is firstname.lastname@example.org, but someone misspells it and sends a message to email@example.com, it will still be received in the catch-all mailbox that you have configured. Just one single mailbox per domain name can have this feature activated and thus you’ll never miss emails because the other side has an out-of-date email address or has made a mistake. The downside of creating a catch-all mailbox is that you may begin receiving lots of junk emails, but this issue can be fixed by using an anti-spam filtering solution. It’s also crucial to remember that a mailbox with an active catch-all feature cannot redirect incoming email messages to a third-party mailbox.