I've just got WHD running here at my location this past week. I'm really just trying to iron out the e-mail setup so I can hopefully launch next week.
Something I've realized is that it seems to require that the user has a log-in that is "firstname.lastname@example.org" in order to receive the e-mail. It is from a domain that is accepted, but until I altered the username from the AD login to the previously mentioned format I couldn't send e-mails that didn't get rejected.
Has anybody had similar issues, and what did you do about it? Thanks!
cnayback-mmg, have a quick look through the Web Help Desk Admin Guide; there are a few links to e-mail setup and maintenance.
Web Help Desk (WHD) - Updated February 14, 2014 - Administrator Guide > Setting Up Web Help Desk > Setting Up Email >
Hopefully your answer lies within. If not, please come on back and we will get you sorted.