Sounds like possibly you have a virus. There's awell known virus that keeps reopening LW after it's shut down and that maybe why your getting the launcher error. Even though you uninstalled LW the virus is still trying to launch it.
See this thread:
WARNING: Viruses on network you should be aware of!. It has lots of info and helpful links. Go to
Norbies World, point 5) in that link. For free comp. help.
If that's not it, then I don't know.