A catch-all e-mailbox is one that gathers all the messages sent to non-existent addresses. For example, if your address is email@example.com, but somebody miswrites it and sends an email message to firstname.lastname@example.org, it will still be received in the catch-all mailbox that you have created. 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 obsolete email address or has made a spelling error. The downside of having a catch-all mailbox is that you may start receiving lots of spam emails, but this issue can be solved using anti-spam filtering software. It’s also important to bear in mind that a mailbox with an activated catch-all feature cannot forward incoming emails to a third-party mailbox.