I have a Hotmail account and therefore I assumed I have a Live ID. If this is correct then why can't I sign in to Windows Community to ask a question?

I can sign into my Hotmail account fine. When I go to Windows Community there is a "Sign In" button on the top right When I click on that nothing comes up -- no "Sign In" box. It just brings me right back to the Windows Community page I was on and still says "Sign In." I can read posts but can't reply to one or start a new one because I can't sign in. Maybe I'm not understanding this Live ID business right???