scottyboi
The post from ukbobboy01 is correct allot of people post and do not supply enough info. Also I looked at your post the day you posted it and quite frankly I have never seen this problem before
and most of us senior members try not to answer if we do not have a good idea of what might be wrong.
With the information you supplied after ukbobboy01 asked I can see that your computer is good enough and should have no problem running LW. Also I see you had no problem with a earlier version of LW but I do not know which version there are allot of other ones.
XP 2002 was service pac1, Are you now running service pac2 who knows you do but I don't. If it is 1 windows doesn't have a built in firewall 2 does.
Your router has a firewall did you configure it correctly follow the instructions exactly. Your router is not one of the easier ones to configure.The first link will tell you how to set up a static IP address. You must do this first. Do everything here there are 2 pages of steps for setting up the static IP address.
http://portforward.com/linksys/wrt54g-dhcp.htm
After you have completed the steps above do the steps in the link below.
http://portforward.com/linksys/wrt54g-dhcp.htm
I do not know if this will correct your problem but it will properly set up your Router. Your problem may be a install problem. I have never seen that message prior to limewire loading and starting up.
Please post back and let us know if it works if it doesn't you may have to un install LW and then manually edit your registry. Other members may have some other ideas or may have seen this problem before. But this is the first time I have seen this one.