Again - in recent updates Microsoft has made the firewall service dependent on the Universal Plug and Play (UPnP) service where it was not before, you need to go the the control panel, administrative tools, services applet and stop the firewall and UPnP services. Give that a try if you have not already.
*mini-rant: Also double check that no other new "security" software has snuck into your system somewhere with updates, it is more and more difficult to use a computer these days as our "security" software slowly cripples them all for us, one by one, and with little to no notification of what is happening... If the AV you have is Norton or McAfee, forget it, it is not your computer anymore...