? is for file type. Not sure why that would disappear .. or why it should make any difference. Have you tried swapping skin & see if that makes a difference & swapping back also

Alternative I can think of is deleting your LW preferences folder. But that means you need to set all your settings again. http://www.gnutellaforums.com/window...tml#post183932. And should only be done whilst LW is closed.