Hi Kushdili.
This link should help you, there are many good links, thanks to Lotr.
Pay attention to BITZI link, Bitzi is your best friend,learn to use it n
it will save you a lot of waisted time.
http://www.gnutellaforums.com/showthread.php?t=63993
Now you say you changed nothing, If you reinstalled L/W then you may need to
reset your options, and firewall port settings.
Is your XP firewall turned off ?
Sometimes you just have to delete Permisions in Norton, Then re apply.
Let us no how it goes.
Also check this link.
http://www.gnutellaforums.com/showthread.php?t=63993
Peace.