You mean that LW isn't opening at all? Try the following:

What version of Java are you using? Try this version. 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 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.
In case you're using Vista: http://www.gnutellaforums.com/genera...der-vista.html

Change compatibility (point 5 in the 'fixes' thread). If you're using XP, try compatibility mode for Win 2000 or NT. If you're using Vista, try compatibility mode for XP.