A catch-all e-mailbox is one that captures all the email messages sent to nonexistent addresses. For instance, if your email address is email@example.com, but somebody misspells it and sends an email message to firstname.lastname@example.org, it will still be received in the catch-all mailbox that you have set up. Only one single mailbox per domain can have this feature activated and thus you will never miss messages because the other party has an obsolete email address or has made a spelling mistake. The negative aspect of having a catch-all mailbox is that you may begin receiving lots of junk messages, but this problem can be rectified using an anti-spam filtering solution. It is also important to remember that a mailbox with an enabled catch-all feature cannot forward incoming emails to a 3rd-party mailbox.