Multiply e-mails? You mean checking multiple e-mails in hotmail, in your web browser? You might want to re-install your web browser if that's the problem.
You may also want to scan your computer. Try a complete system scan with
SuperANTISpyware (It's free, though it doesn't offer real-time protection so don't rely on that as your only antispyware/adware/virus from now on
)
Other than that I don't really see what could be causing the problem.. unless your account has been accessed by someone.. try changing your password + secret question/answer + alternative e-mail