Hmmm !!!!!!!!!!!!!!!!!!!!! ?????????????????????

er, if you are using the same computer (that won't 'allow' LimeWire to connect) for accessing the internet and these forums, than the probability (very high) is that you are doing so through port 80...
(btw - Never configure anything but your browser to use port 80.)

So, if the above is correct (keeping in mind that you said that the scan you did reported that ALL ports from 0 to 65000 were not open), how are you having these pleasant chats with all of us, now ???

I think the first thing to do is to remove the URL to that site from your favorites !!!

I note that no one has yet asked you the current 'silver-bullet' question:
Have you recently 'updated' or fresh installed LimeWire ?
If the answer is, "Yes," than we probably move into other issues and perhaps a fix.

Big question is always, "What's changed ? What is new ?"

Hang in there !

p.s. You might want to see this > Alternate PORTS for a bit more 'background' info.