Try downloading and installing it again.
To uninstall properly, make sure limewire is shutdown completely and not still running in the system tray. Don't use the add/remove programs to uninstall. Go to the program folder, it should be found at C:\Program Files\LimeWire\Uninstall.exe. Double click the Uninstall.exe file. That should uninstall it.
Then search your hdd for LW and delete any references.
If your still having troubles go over
NorbiesWorld. He offers free computer help and he'll check your computer.