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any media file stored on the desktop, in the document folder, in the movie folder, etc.
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However, you could just as easily have left this "System Preferences" option set and over-ridden the iCloud window targets by simply selecting an alternative navigation target on your local drive-e.g.
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Yes, it is true that turning off the "iCloud > iCloud Drive > QuickTime Player.app" option will prevent the automatic opening of either the "iCloud Drive" or "QuickTime Player-iCloud" folder window. Instead, when the "iCloud > iCloud Drive > QuickTime Player.app" option is set in the "System Preferences" window, the "iCloud Drive," "QuickTime Player-iCloud," or the last used "local drive" navigation window opens automatically so you can select a media file for playback. If, as you keep saying, the "iCloud Drive" or "QuickTime Player-iCloud" window opens, then QTKirk is correct in that the QT Player app has actually launched but you are equally correct in that no media player window is automatically opened. I suspect the primary point of contention between you two is what "the QuickTime app did not launch on the desktop" actually means. Still, you didn't understand the problem, which was the Quicktime app did not launch on the desktop.
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