Thanks for all the excellent advise. I completed all of the steps. Still having a problem with my rberry@cadcourse.com. Even though I've created a contact for this e-mail address and use it in the e-mail, still the same result (below), sorry. None of my e-mail addresses use the mailto: prefix, just the straight emailaddress@domain.com.

Boy, this is so odd! Thanks for your help! All my best,
John

Your message did not reach some or all of the intended recipients.

Subject: TurboCAD v19 Primer?
Sent: 3/15/2012 8:21 PM

The following recipient(s) cannot be reached:

Rob Berry (rberry@cadcourse.com) on 3/15/2012 8:21 PM
None of your e-mail accounts could send to this recipient.