AsMask 2.6
AsMask can encrypt and hide all format secret files or text messages into an image. Encryption method based on 256-bit encryption algorithm. The solution is reliable and you can set a password to protect the encryption files and text messages. You can view the image hidden files and text messages as same as normal image. Nobody can aware of messages hidden in the image. AsMask can hide files and text messages into any format images.

ap PDF Encrypt 3.0
PDF Encrypt software is a very flexible and powerful program, PDF Encrypt software allows you to encrypt (using standard 40-bit or 128-bit or AES encryption ) existing PDFs, set permissions, add user and owner password. For example you can encrypt a PDF without to allow to print it.

PDF Encrypt COM/SDK 3.0
PDF Encrypt software is a very flexible and powerful program, PDF Encrypt software allows you to encrypt (using standard 40-bit or 128-bit or AES encryption ) existing PDFs, set permissions, add user and owner password. For example you can encrypt a PDF without to allow to print it.

PDF Encrypt COM/SDK Unlimited License 3.0
PDF Encrypt software is a very flexible and powerful program, PDF Encrypt software allows you to encrypt (using standard 40-bit or 128-bit or AES encryption ) existing PDFs, set permissions, add user and owner password. For example you can encrypt a PDF without to allow to print it.

LockLizard Safeguard PDF Security 2.6.29
PDF document security software with US Government strength encryption and DRM digital rights management controls. Control who can view your PDF documents and how they are used. Stop copying, sharing, modifying, and screen grabbing. Control the number of views and prints or disallow printing altogether. Control when documents expire and instantly revoke them. No useless pdf password security. Complete PDF copy protection and PDF control.

CryptoLab 1.02.2
CryptoLab is a freeware cryptography application for Microsoft Windows, and incorporates text-based encryption / decryption through the use of plug-in cipher modules. Advanced features include: Plug-in cipher modules; Advanced pseudo-random key generation; Key Manager storage utility; Full password protection; Integrated SMTP email support; PDF, HTML and Word Document export options; Statistics calculator.