Microsoft email account invalid err message


New Email
I am using IE8 on win 7,
Cannot log in to my hotmail email acct. err msg reads "Microsoft account is invalid".
I can and have sent emails to my hotmail acct. I have also verified my acct exist.
I have read the forum and have not been able to resolve this problem.
I successfully logged into my hotmail email acct. two days ago.
Please help me.

Signed Missionunite