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Unable to play mp4 files

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  • Last reply by FredMcD

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I don't know if this is a Firefox problem or Windows 10. When I receive an mp4 file in gmail on the browser and click on it, it doesn't seem to know what to do. The file association in my windows version is set to play them with the microsoft app, and I can play the video if I download it first. The error message is attached; Any comment ????

I don't know if this is a Firefox problem or Windows 10. When I receive an mp4 file in gmail on the browser and click on it, it doesn't seem to know what to do. The file association in my windows version is set to play them with the microsoft app, and I can play the video if I download it first. The error message is attached; Any comment ????
Attached screenshots

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Give this a try; http://www.videolan.org/