Eudora email trubbles;Might be looking for something better!

Howdy Folks...
I've been using Eudora for years now, and liked it! However, a month or so ago I was requested by my ISP (Mindspring/Earthlink) to change my settings (re:SMTP). Did that, had probs, finally ironed it all out (turns out it had to do with SSL settings). NOW....

...most recently, I've found I cannot send certain emails, keep getting a "closed by foreign host" message. These emails tend to be ones that I'm replying to and sometimes are ones I create. It's so weird, especially 'cus I can send myself an email and also send an email to my other email accts (Hotmail) but yet can't get them sent to others.

I've gone to the Eudora online help forums, see others posting with probs similar. Very few people are getting results. (One person states he paid for the upgraded mode and STILL had the same problem; glad I saw that, it saved me some moola.)

At this point, two questions:
(1)Has anyone else had trouble with Eudora regarding sending emails, and if so, how did you resolve it?
(2) Does anyone know of a more user-friendly email system that can be used AND has no glitches? ( I have a hotmail acct; should I just create a second one for handling my other emails that pertain to business?)

I'm so perturbed with Eudora as well as my ISP (Earthlink); can't seem to get any help from either of them.
Heck, right now I"m even thinking of going to another ISP.

(Oh how I long for the day when Dave will create an email system that can be used outside of DG!)