Well if you are using Windows XP, which I am not assuming you do, there is a port that by default is activated called Universal Plug and Play.
My suggestion because nothing works is uninstall the UPnP feature and see if that helps.
http://www.grc.com/unpnp/unpnp.htm This is an easy way of disabling it. Basically just run this or you can go into add and remove programs and under windows components it can be uninstalled.