Abstract: A file encryption method is provided which includes the steps of encrypting the text of the message to be sent, concatenating the encrypted text together with a password to the end of a decryption application to produce a combined file and converting the combined file to an electronic mail format. The file encryption method further includes the steps of transmitting and receiving the converted combined file, reconverting the converted combined file to its previous format and executing the combined file thereby to operate the decryption application on the encrypted text and thereby to produce the text of the message.