it shouldn't be. I'm running Vista Ultimate on my new Toshiba Laptop and I have Limewire 4.16.6 installed and everything is running perfectly.
Have you altered the screen resolution or anything else in Vista that might have upset Maybe you could try installing the latest non-beta edition which is 4.16.6. Get it from the official LimeWire homepage and install it after you haveuninstalled the previous version (including going into your C:\ directory and deleting any LimeWire folder from there) A good idea is to read as many of the "sticky" posts as you possibly can.
Quite often people have found solutions to their problems somewhere in these posts.
Good Luck!

Thanks, but I gave up!
Dunno what happened, but LW is no more working on my Vista.

I had the same problem and uninstalled java and reinstalled it. I also disabled pop up blocker in windows ie7. Then after that I installed limewire and now it works. One other thing - It changed my color scheme temporarily because its not compatible with Vista aero. Very Strange..... and it still won't install frostwire but I'm happy with my outcome thus far. The funny thing is limewire was working fine then all of the sudden a week or two ago it crashed on startup. Hope this helps.