Thanks for that. Unfortunately, I don't think I explained myself clearly enough in the first place (D'Oh).
I'm using Borland 5.5, not Builder, and MapiSendMail is the function that causes the problem (when linking).
I get the same problem when trying the same with MinGW.
I'm a little bit new to C/C++, so forgive me if there is areally obvious reason why I can't do this. I'm thinking that I might need a newer/different .def/.a as I can't find MapiSendMail in any of the ones I have.
Up until now I've been using:
ShellExecute(hWnd,
"OPEN",
"mailto:a@b.com?subject=subj&body=message",
0, 0, SW_SHOWNORMAL);
It's a bit of a bodge though, and I can't see how to send attachments like this.
Any other means of sending email that uses the default client would be fine, it doesn't need to be MAPI.