Box Trapper is a powerful tool for fighting spam. It maintains a "white list" of addresses. Anyone who sends you mail and who is not on the white list needs to complete a verification process before their mail will pass to your in box.

Since almost all spam comes from forged mail addresses, this verification system fails and the message is never cleared for delivery. After a period of time, the spam is automatically deleted.

This is how the Box Trapper system works:

  • Every new message you receive is compared against three lists.
    • White list messages pass directly to your in box.
    • Ignore list messages are deleted with no notification.
    • Black list messages are deleted, and the sender receives a reply indicating that the message was blocked.
  • If the message is not on any of the lists, the message is held and Box Trapper sends a coded verification challenge to the sender.
  • The sender receives the challenge and simply replies to it.
  • Box Trapper receives the challenge reply, verifies the code, and if there is a match, it passes the message to your in box and adds the address to your white list.
  • All future messages from this sender pass through the system automatically.
  • Messages are held by Box Trapper for a period of days so that the sender has sufficient time to see the challenge and reply. After this period, unverified messages are deleted.
Box Trapper works because most spam comes from forged mail addresses. When the challenge message is sent to the forged address, it is never received. There is no reply to the challenge, and the message is never delivered.