I am having the same problem and I also noticed that while Limewire is running trying to connect in the background I cannot surf the internet unless I shut down Limewire and right click the icon and exit. Then and only then can I access the internet. I had installed the Internet Explorer 7 beta 3 and thought Microsoft was trying to be funny and slip something in there but I uninstalled it (%windir%\ie7beta3\spuninst\spuninst.exe), restarted and I still have the same problem and test port 6346 worked.