A method and system for confirming proper receipt of an e-mail file sent by a sending party over a communications network such as the Internet and intended to be received by a target party. The e-mail file sent by the sending party is properly or improperly delivered to a recipient e-mail address and stored in a data storage location of a recipient computer system. When the accessing party, who may or may not be the intended target party, accesses either the e-mail file itself or an e-mail processing program or user account, various recipient information, including identity information associated with the accessing party, is discovered from the recipient computer system and included in a generated confirmation of receipt notice. The confirmation of receipt notice is subsequently and automatically return transmitted to the sending party. In one embodiment, an attachment file is transmitted together with the e-mail which operates to discover and obtain the recipient data, generate the confirmation of receipt notice, and transmit the confirmation of receipt notice to the sending party. In this manner, the sending party can determine whether the accessing party who actually received and was notified of the e-mail file was in fact the intended target party, and thereby determine whether delivery was proper.