this could be it.
at my company we have numerous mailboxes that are purely viewed and
processed elsewhere in the company. when we first set up the mailboxes we
logged in on the server setting them as a primary mailbox. on that, we then
set an Out Of Office message saying, "thank you for your email...etc, etc".
this will class as the receipt that i think ks is referring to, and indeed
that Milly suggested.
hth
"Milly Staples [MVP - Outlook]"