Fortress Mail allows you to encrypt your outgoing email messages. It uses your existing email program (such as Outlook, Outlook Express or Eudora) via MAPI to send and receive encrypted messages and attachments. Fortress Mail uses the Advanced Encryption Standard (AES) and HS1 to make sure that your messages are safe and cannot be cracked. The program is fairly simple to use and provides a very basic interface. The receiver of the encrypted messages must have the valid password and also a copy of Fortess Mail installed in order to decrypt your message. Additional features include an integrated authentication database. Fortess Mail is compatible with most protocols including POP3, IMAP, SMTP, ESMTP and X400, however only works via MAPI.