I guess you've tried the fixes here.
If LW Will Not Connect

When you replaced the gnutella.net file, did you make sure that LW was properly closed? Otherwise it won't make any difference.
When you updated Java, did you make sure to remove any other Java versions that were installed on your computer before installing the new one?
When you deleted LW's preferences folder, did you look for a folder in both the old & new locations?

If nothing's working, we'll need your system details.