Read the forum guidelines
I just read this forum post from unhappy customers with the same problem I'm having, so I know I'm not going to get any help from Cox here...
http://forums.cox.com/forum_home/internet_forum/f/5/p/666/1889.aspx#1889
Apparently you're happy to promise that your web mail works with Windows Live, but when it doesn't, oh well. I can get Windows Live to receive mail, but it won't send. I get the same kind of error messages everyone else reports.
I followed these instructions for setting up the email client:
http://ww2.cox.com/residential/support/internet/article.cox?articleId={a8fb24c0-6440-11df-ccef-000000000000}
I also followed these different instructions:
http://ww2.cox.com/business/idaho/support/data/article.cox?articleId={f808a330-6b56-11e0-4e73-000000000000}
I also tried the Default settings in Windows Live. Nothing.
I used "chat" for help. No help. I called Tech Support. After the lady checked my settings and it still didn't work, she directed me to Super-Duper Tech Support. After waiting on hold for however long, Super-Duper Tech Support said they wouldn't help me, because apparently Super-Duper Tech Support is a paid service. I did the requisite screaming, but the guy still told me to call me local tech support in the morning to complain, then gave me a "local" number that isn't even in my state.
Dear Cox: F*CKING FIX THIS!
Chris, thank you. I'm not sure why the tech directed me to the page with the coxmail.com instructions, but reverting to the other and deleting the outbox contents did the trick. Thank you!