Have a look at your ZoneAlarm firewall and see if you have it configured properly
User Cant Connect - LimeWire
You could also try deleting your preference folder and see if that helps...
Fixes for Limewire when LW isn't operating as it should
Java could be a possibility as well so you could try uninstalling your Java from the add/remove programs and then re-install the JRE 5.11 offline version....
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11
If those solutions don't work what is the make and model number for your modem/ router ??