The files should still be on his hdd just no longer in his library. Try searching for the files by going to Start>Search>All Files and Folders, and search for the title of some of the missing files.
Once you find their location, you can add the folders to his LW library by opening LW and going to Tools>Options>Sharing, and adding the folders from there.
Look here if you just updated to the latest version of LW:
http://www.gnutellaforums.com/downlo...downloads.html