A catch-all email mailbox is one that collects all the email messages sent to inactive addresses. For example, if your address is firstname.lastname@example.org, but somebody miswrites it and sends an email to email@example.com, it will still be received in the catch-all mailbox that you have created. Just one single mailbox per domain name can have this feature enabled and in this way you’ll never miss emails because the other side has an out-of-date email address or has made a spelling error. The downside of having a catch-all mailbox is that you may begin receiving a lot of spam, but this issue can be rectified using an anti-spam filtering solution. It’s also crucial to keep in mind that a mailbox with an enabled catch-all functionality cannot redirect inbound email messages to a third-party email address.