Try updating to the latest version of Java here (I have this one & LW's working fine):
Java SE Downloads (4th one down)
or try this older version, which has worked well for lots of people:
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11 Whichever Java version you use, download the JRE offline installer & Remove any other Java versions before installing another one.