Just give it a try see if any luck when you found a MP4 video can’t be opened in QuickTime Player on Mac. QuickTime Player video supportĬhange extension from. We recommend MP4 with h.264 or h.265 codec for great compatibility with various devices and even online browsers. In such case, you can either use a more powerful media player with the codec support or transcode the video to a compatible codec, such as H.264. If the QuickTime Player won’t play a MP4 video, most likely the video is compressed using an incompatible codec. It is like a box that contains your video, audio, and metadata. Why MP4 videos can’t be opened or played on Mac? Other MP4 & video conversion alternatives.Convert videos using VLC media player on Mac.View video codec in VLC player - optional.Why MP4 videos can't be opened or played on Mac?.

But why the QuickTime Player can play some MP4 files, not others. We all know that MP4 is the industry standard, the most popular video format and QuickTime Player is the default app to open and play MP4 files on Mac. Failed to open a MP4 file on Mac? MP4 video is not compatible with QuickTime Player?

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