Do both steps #1 & 2 here: Try deleting your LW Preferences folder whilst LW is
closed; instructions here:
Point #2 in Fixes for Limewire (sample at bottom of page.)
Yes, re-install Java again but ONLY using the "Offline" installer version. Installing over the net can cause problems.
BTW if you can't find your LW prefs as described, then LW 4.10 is probably your 1st version of LW. In which case the preferences folder will be found here:
How to delete LW preferences folder in 4.10 (click on link) Don't forget to set the view options to show hidden files & folders before you search for limewire!