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mp4 plays in firefox on one computer not another

  • 5 ŋuɖoɖowo
  • 3 masɔmasɔ sia le wosi
  • 1 view
  • Nuɖoɖo mlɔetɔ lcscherzer

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I've put a simple mp4 slideshow on a webpage. On one computer (windows 10 pro) Firefox shows and runs the mp4 fine. On another computer (also windows 10 pro) Firefox shows the message "Video format or MIME type is not supported" in place of the video.

Using Edge the results are the same. First computer runs fine, second gets Edge message is "This type of video file isn't supported".

I'm guessing the second computer is missing something. But what?

In all incidences I'm simply running the file locally, not from on-line.

Thanks

I've put a simple mp4 slideshow on a webpage. On one computer (windows 10 pro) Firefox shows and runs the mp4 fine. On another computer (also windows 10 pro) Firefox shows the message "Video format or MIME type is not supported" in place of the video. Using Edge the results are the same. First computer runs fine, second gets Edge message is "This type of video file isn't supported". I'm guessing the second computer is missing something. But what? In all incidences I'm simply running the file locally, not from on-line. Thanks

All Replies (5)

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Make sure one doesn't have the "N" edition of Win10.

for the one that isn't working, go and update the videocard drivers direct from intel/AMD/nVidia then restart.

Start firefox and type "about:support" in the url and then click "refresh firefox" and it should now work.

If the problem was that you had the "N" edition, you need to manually go and download the windows media foundation codecs and install them.

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This article has the download link for Media Foundation components: Fix video and audio problems on Firefox for Windows N editions.

If Windows says it doesn't need that, could you check this test page and see which boxes are red:

https://www.youtube.com/html5

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The youtube link shows mse webM vp9 with a red exclamation mark

I don't have version N of windows 10.

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lcscherzer said

The youtube link shows mse webM vp9 with a red exclamation mark

That's normal; if you have H.264 support you should be able to play the file.

I can't think of any setting that would block MP4 locally but not on a webserver. Is there any difference in security add-ons between the two Firefoxes that could explain it?

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Shouldn't be. Working system is a desktop and non-working is a laptop. The actual webpage is on the working system. Other is networked. All this is offline because my web host doesn't support mp4. Thanks for your help