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Quicktime won't open up my MP4 file

I recently transferred my MP4 files to my G-Drive because I do a lot of editing and was running out of space on my Mac.... Everything was fine until I plugged in my hard drive the next day and found my MP4 files thumbnails showing up white instead of the usual MP4 QuickTime thumbnail it usually has. Every time I try to open it, it says that it either can't find an app to open it with or that Quicktime can't open the file. Is this a lost cause? Are the files completely gone forever or is there a way to fix this?

iMac

Posted on Mar 15, 2018 10:17 AM

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Quicktime won't open up my MP4 file

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