What brand & model of wireless set up do you have?
Also, do you see a brick wall in front of the blue world icon at the bottom of LW's interface?
Is XP firewall turned on or off?
1st try this: Try deleting your LW Preferences folder whilst LW is
closed; instructions here:
Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.)