A method and system for encrypting an electronic message to a receiver by utilizing a sender generated ad hoc asymmetric key pair whose private key is encrypted and known only to the sender. The key pair is uniquely associated with both the sender and the receiver and is stored in a key server. A method and system for decrypting an encrypted electronic message by authenticating the receiver to the sender and having the sender retrieve and decrypt the encrypted private key. The above methods and systems utilizing an ad hoc symmetric key instead of an ad hoc asymmetric key pair.