Crash thanks for the info: yep, confirmed SMTP & POP3 server names with ISP, for the rest their helpdesk was... well... more desk than help. I do indeed use other ISP's on my travels (with my W98 laptop, accessing my mail via webmail), but the machine in question is my home XP desktop, with only one account defined. I'm not sure either why OLE works and OL doesn't.
I assume that the relaying in question is outbound from my ISP, if I send a mail to myself it works fine. Also the [Test Email Settings] on the "Internet EMail Settings (POP3)" screen works fine every time.
Hold the phone... on the same screen, [More Settings] which I went to before [Outgoing Server] tab to say that my SMTP server requires authentication, for some reason under [Connection] tab I have "Connect using my Local Area Network (LAN)" selected. Change to "Connect using my phone line" and the problem is resolved? OK for a couple of test messages, so we'll see.
Assuming that fixed it, thanks guys for pointing me in the right direction. I consider myself reasonably IT literate at least as far as your average aviator goes, but some of these options are buried pretty deep, and the error messages don't help much.
Maybe I'll have Calendar after all.
-ev-