If you are not able to connect to LW then try the following:

Uninstall LimeWire. Then Uninstall Java.
Download the latest versions of both the softwares i.e. 4.9.30 and 1.5!!
Manually delete the .Limewire preferrence folder!

Install Java 1.5 first and RESTART!
Install LimeWire 4.9.30/Pro and again Restart!!

Disable any other Firewall software tht u have and keep only Windows XP SP2 Firewall ON!!

LimeWire will start working with highest possible speed i.e. excellent / Turbo-Charged for Pro!!!

This worked for me since Norton Internet Security's Firewall was blocking LW even when I had given 'Permit ALL' to it!!

Dont forget to RESTART!!

GOOD LUCK!!