A data encryption/decryption system is provided which encrypts a critical file to a software program using an embedded executable. The executable programs a user computer to prompt a user to purchase a license key to decrypt the critical file in order to run the software program....http://www.google.es/patents/US6223288?utm_source=gb-gplus-sharePatente US6223288 - System for persistently encrypting critical software file to prevent installation of software program on unauthorized computers
System for persistently encrypting critical software file to prevent ...
