Double check that you're only using 1 software firewall & that it's configured properly
Firewall setup
Otherwise, try removing your current Java version & reinstalling JRE using the offline installer. Point 1 below. Also try deleting the preferences folder when LW's closed, points 2 & 3 below.
Fixes for LimeWire
If this doesn't help, check that it's not a firewall within your modem/router causing trouble. Double check your UPnP or port forwarding setup.
Connection problems? Check here first!