Can't get email address installed on iPhone

I had another thread going, but I inadvertently hit the "select" button rather than the "reply" button. So here we go again. My wife's email account suddenly stopped working on her iPhone. So I removed the account from her phone. When I tried to add it back, the phone says that either the username or password is wrong for "imap.cox.net". I'm sure they are correct, as I can access the account using webmail. I tried some very different settings (including "imap.coxmail.com" and "smtp.coxmail.com") that someone sent in the other thread and they didn't work either. I think I need a little hand-holding. Thanks. Wayne.