My Finder still shows all applications twice or even three times in the context menu for a file in the Open With submenu. And I can't figure out for the life of me how to fix this. Hasn't anyone else had this problem? There must be a way to clean it up, after all, the menu is dynamically created by OS X from the installed applications - but there must be some kind of type registry somewhere where applications register themselves so that OS X knows they can read this file type. And that's the place you should be able to clean up. But how in the world do you do that? Where does OS X remember which programs can open which file types?