Ariel1998: If you haven't already, configure your firewall for LW's access:
http://www.limewire.com/english/content/firewalls.shtml
Try deleting your LW preferences folder whilst LW is closed; instructions:
Fixes for Limewire
Open LW, go to Tools>Options>Connections & untick option to Connect on startup & press the Apply button. Go to Tools>Options>Advanced>Firewalls & make sure UPnP is ticked. Now close LW. Re-open LW & leave it for 15-20 mins. Then go to LW's menu File>Connect & give it 15-20 mins to connect. Good luck.