Patent ID: 8649522

Claim:
A system for communicating an electronic mail message to a recipient, the system comprising: a network having network devices connected thereto, the network devices including a mail registration server and a plurality of user computers, wherein encryption data for encrypting an electronic mail message into an encrypted electronic mail message is encrypted to form encrypted encryption data and the mail registration server is operable to store a tracking key required to decrypt the encrypted encryption data, the tracking key being employed in a user computer associated with a sender of the electronic mail message to generate an intermediate key, wherein a user computer associated with a recipient of the encrypted electronic mail message is operable, following receipt of the encrypted electronic mail message, to: (a) send the mail registration server a digital signature generated using a private key of the recipient before being able to receive the tracking key from the mail registration server, (b) receive the tracking key from the mail registration server, (c) decrypt the encrypted encryption data using the private key of the recipient to form the intermediate key, (d) use the tracking key received from the mail registration server to convert the intermediate key to a session key, and (e) use the session key to decrypt the encrypted electronic message, wherein the mail registration server is operable, following receipt and verification of the digital signature generated using the private key of the recipient, to provide the tracking key to the user computer associated with the recipient.