In Outlook(not Express) email options you have the choice of 2 separate receipt options. The 1st is "Request a delivery receipt for this message" which is responded to by the recipient "mail system" or so I am told by Microsoft Certified Engineers. The 2nd is "Request a read receipt for this message" which is responded to by the "recipient" at the time of open/delete of the actual email. This is the message, the 2nd option, that is generally suppressed by individuals or by company policy such as to NOT confirm individual email addresses. This, the 2nd option, is also the receipt that Adagio is requesting.

As I understand, the 1st receipt indicates that a recipient "mail system" has accepted the email but does not confirm delivery to the recipient. It only confirms the "hand-off" to an upstream system.

My question to your response "The Internet does not support any confimation ..." then what was the intent of the "Request Reciept" box on Line 2 of Email Setup in Invoices?

Something tells me we are talking at cross purposes and not communicating correctly.