How InBoxer works InBoxer starts by creating two new folders for you in Microsoft Outlook: InBoxer-Blocked and InBoxer-Review. InBoxer never deletes a message. Spam and unwanted email messages are placed in the InBoxer-Blocked folder when new mail arrives. InBoxer learns by example. Questionable messages are placed in the InBoxer-Review folder for you to consider. If you check the InBoxer-Review folder regularly, InBoxer will quickly become even more accurate.