Are you using Windows Live OneCare?
If not, you're off topic for this forum, which is dedicated to Windows Live OneCare.
If you are using OneCare, try turning off the OneCare firewall. I suspect that you will not see any change. If it does work, though, you will need to determine what the site is using in order to allow it through the firewall. You may need to contact the site for support information.
OneCare support can be reached through here:
How to reach support (FAQ) - http://forums.microsoft.com/WindowsOneCare/ShowPost.aspx?PostID=2421771&SiteID=2
-steve