A record of a document is transmitted to a receiver so as to provide proof of transmission of the document by delivery of the to be transmitted document to a secure delivery box which provides a copy of all documents being transmitted to the sender and/or the recipient and/or the service provider of the delivery box by a hard copy or electronic copy of the documents inserted into the delivery box with the sender's address being visible through a transparent window of the to be delivered document or entered by an external keyboard of the delivery box so that copies and confirmation of delivery of transmitted documents is achieved.