A computer based message encryption system for transmitting encrypted message between a sending member of an internal messaging system and a receiving non-member or receiving member external user without requiring the sender or recipient member to maintain and support encryption key pairs themselves. An internal system that contains an external server for creating key pairs for message encryption between the senders and receives for the encryption of messages. The key pairs are encrypted themselves according to an encryption pass-phrase so that the pass-phrase may used to decrypt the key pair which in turn may be used to decrypt the message. In response to a predetermined time or destroy command, said encryption key pairs are destroyed.