Hello,
I had the same problem trying to get to www.hotmail.com a few weeks ago from work. They have changed the site somehow (not had time to look into yet) that it wants to use that passport authentication when logging in. I can get to the site fine, just not logon. It works fine at home .... so my question is: Are you behind a firewall like I am at work? If so you may want to review its settings.

Good Luck.