Patent ID: 7418737

Claim:
A computer program product, embodied on a computer storage medium, comprising a computer program operable to control a first computer to encrypt a computer data file and to create decryption control information for said data file, said computer program comprising: encryption logic for encrypting said data file to create an encrypted file and for creating a decryption key for said encrypted file, said data file comprising a text file and said encryption logic converting said text file to at least one graphic formatted image prior to encryption; transmission logic for controlling said computer to transmit said decryption key to a remote location; and application creation logic for creating an executable application for controlling decryption of and user access to said encrypted file on a second computer, said executable application comprising: retrieval logic for retrieving a decryption key stored at a remote location, triggering deletion of said decryption key from said remote location, and retrieving decryption logic, user access logic and deletion logic, said decryption logic for decrypting said encrypted file using said decryption key to create a decrypted file, said user access logic for providing user access to said decrypted file, and said deletion logic for triggering deletion of said decrypted file, said encrypted file and said executable application on termination of user access to said decrypted file; wherein output devices not involved in said user access are disabled during said user access to said decrypted file; wherein input devices are disabled during said user access to said decrypted file; wherein said user access logic provides said user access to said decrypted file for a predetermined period of time, and said deletion logic deletes said decrypted file, said encrypted file and said executable application on expiry of said predetermined period of time; wherein said retrieval logic is operable to request input of access credentials and compare said access credentials with credentials stored within said executable application, and, upon said access credentials matching said stored credentials, to proceed to activate said retrieval logic to perform further processing.