How the SMTP handshake becomes your proof of delivery

When people ask what MailProof actually records, the answer is the SMTP handshake — the standard conversation that takes place between two mail servers whenever an email changes hands.

Every certified email is routed through MailProof's certified relay servers rather than sent directly. As the relay hands your message to the recipient's mail server, it captures that server's replies: the acceptance confirmation and the exact timestamps at each point. This is the same low-level exchange that governs all internet email, so the record reflects what the recipient's own system did, not merely what MailProof intended to happen.

That captured data is what makes a MailProof certificate independent evidence. It isn't a claim that we posted the message and hoped for the best — it is a log of the recipient server accepting responsibility for the message, with times attached. The relay then turns that log into the delivery timeline you see on your PDF certificate.

Because the evidence comes from the handshake itself, you don't need the recipient to cooperate, reply, or hold a MailProof account for the proof to be valid.