Try LOTR's fixes here
http://www.gnutellaforums.com/showth...ight=wont+open

Try reinstalling Java using the manual (offline) installation & deleting the preferences folder (all the info's in the above thread)

If you're going to reistall both Java & LW, install Java first.

The other thing that could be a problem is if you're using antispyware which might be seeing LW as a threat. Have you installed or updated any antispyware lately? If so, make sure that LW's on the list of exceptions/allowed apps.