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Question: QuickTime Player can't open "file.mp4"

My husband completed a movie in iMovie 10.0.5. When he tries to open said movie in QuickTime Player 10.3 he gets a window that says,

QuickTime Player can open FlyIn.mp4 (FlyIn is the name of the movie, obviously). We tried QuickTime Player 7.6.6 found in Utilities

and the mp4 is not even recognized so we can attempt to open. He's running Mavericks.😕

iPhoto '08, OS X Mavericks (10.9.3)

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Sep 13, 2014 2:53 PM in response to vicki145 In response to vicki145

QuickTime for some odd reason doesn't support .mp4 even though that is, as I'm sure you have figured out, the file type that iMovie uses to export projects. Try converting the movie to one of these supported movie formats. I recommend using "Smart Converter." It is free for download in the Mac App Store.

Sep 13, 2014 2:53 PM

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Question: QuickTime Player can't open "file.mp4"