This is what we know
New live mail
Still does not work
Sounds to me that my first answer, with a slight variation, is correct. Mail from Live Mail is not being accepted by Earthlink
They must receive a lot of spam from Live Mail users and thats how they put a stop to it
Have no other ideas or suggestions, except one
You can set up live mail in two ways.
It is sent from your ISP and uses the address of Earthlink or
your ISP allows, it can be actually sent by Earthlink
Find out which you have and try the other if permitted by your ISP
I have an ATT affiliate as my ISP and cannot send via my email. I use my email address but ATT actully does the sending. The SMPT information is that of ATT.