I'm looking for a way to not send an e-mail that confirms ticket creation to a small set of e-mail addresses. We've got a couple systems that I have e-mailing the helpdesk for the creation of tickets. When the system auto replies to their non-valid address, I'm then getting a ticket note with the Failed to Send e-mail generated by my exchange server.
Although I don't use the LS Helpdesk, we had the same issue with our TT system, what we did was to create those email address, but forward them to the null device (this was a Unix server, but Exchange can do that, too), so those emails would get sent, received and them discarded...