I'm about out of ideas - email app

I've posted about this here several times but I'm not making any useful
progress.

Eudora decided it need to be installed again one morning. Installed
Eudora and later Thunderbird for XP.

Neither will connect with the ISP email server

mail.sitestar.net

I verified this name with the ISP several times. Same server for incoming
and outgoing. Ping shows server is present and reachable.

The only other thing I can think of is the wrong port used in email app.
I'm sure they are correct but will experiment today just in case.

Anyone have any suggestions? A Google search phrase? Another email app -
one still in business? I'm sure this is something simple: a stupid
mistake on my part.

TIA


--
I love a good meal! That's why I don't cook.