A catch-all email mailbox is one that captures all the email messages sent to invalid addresses. For example, if your email address is email@example.com, but somebody misspells 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per domain can have this feature activated and in this way you’ll never miss emails because the other party has an out-of-date email address or has made a mistake. The drawback of configuring a catch-all mailbox is that you may begin receiving lots of spam, but this issue can be resolved by using anti-spam protection software. It’s also crucial to remember that a mailbox with an active catch-all feature cannot forward incoming emails to a 3rd-party email address.