A catch-all mailbox is one that gathers all the email messages sent to non-existent email addresses. For instance, if your address is firstname.lastname@example.org, but someone miswrites it and sends an email to email@example.com, it will still be received in the catch-all mailbox that you have configured. Only one single mailbox per domain name can have this feature activated and in this way you will never miss emails because the other party has an out-of-date email address or has made a spelling mistake. The disadvantage of setting up a catch-all mailbox is that you may begin receiving lots of spam, but this issue can be rectified by using an anti-spam protection solution. It’s also essential to know that a mailbox with an active catch-all feature cannot forward incoming email messages to a 3rd-party email address.