>>Yeah, they'll be an entry of the above under HKEY_LOCAL_MACHINE if Outlook Expreess is installed. In fact, all mail clients should be found there.
>
> Why GroupWise is not there? Is it not Mail Client program? Also I checked on another computer. It has an entry of Outlook Express, but it was not properly setup there, threfore it would not work... I'm not sure all our users have Outlook Express properly setup, e.g. filled in all necessary information... What why I have a question: how can I tell MapiMail class (Nigel) to use GroupWise as a mail client?

Outlook Express, I believe installs with Windows.

As for Nigel's class, you'd have to ask him. I'm not familar with it.