This is a forum for various Gnutella clients, LW's just one of them. We're volunteers who don't work for LW

If that doesn't help, delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.

Have you changed your Java version since you updated? Some people have had connection problems when using the latest Java updates. Try this version instead. Download the JRE offline installer & remove any other Java versions before you install this one.
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11

If none of that helps, tell us the brand & model of your modem/router (if you can't see any info on the unit, have a look underneath).