Cant get into hotmail from firefox

Hello,

I cant get into hotmail from firefox. It keeps asking me for my password- and no matter how much I try to put it in, it keeps saying that either the email or password is wrong?

When I use internet explorer- I can get into hotmail, open a message, and as soon as I hit the reply buton i get a message: Internet Explorer has encountered a problem and needs to close. We are sorry for the inconvenience: Windows has encountered a problem and must close down, an ask if I want to send error report.

Help!

Daniel