I cannot send or receive email.  I get the message:  the host imap.mail.yahoo.com could not be found.  Please verify you have entered the server name correctly.

Before that, I got a got a Windows Live Box wanting me to sign in with my Microsoft Account Password and Email address which was there.  Then it would tell me the Username which was not requested and no place in which to enter it, or my Password was incorrect.

I don't know what to do?