Remove duplicates from contextual menus In addition to Time Machine I do a weekly clone of my system drive to a volume on a second hard drive in my 2011 MacBook Pro. I also made a clone in another volume before I upgraded to Lion.
Now some of the apps from the Snow Leopard drive clone are starting to show up as duplicates in &quot;open with&quot; contextual menus.  If I choose one of the duplicates it will open the app from the cloned volume.
How can I remove these items from the menu and make sure OS X doesn't think these are installed apps?
Screenshot:
I had the same problem, rebuilding the Launch Services database did the trick for me. Entered the following in Terminal:

/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain user


Then log out and back in. The open with menu should be clear of duplicates.

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