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mime type not supported on videos

  • 47 replies
  • 52 have this problem
  • 8 views
  • Last reply by Lanselot

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hi , recently i'm having problem on play some videos receving the error that mime type is not supported and also i can't view videos on socials like twitter , im using this site for testing http://www.quirksmode.org/html5/tests/video.html and the video i can't view is the first H.264/MP4 here a image of the error http://i.imgur.com/Vb1QJXq.jpg im on windows vista 32 bit service pack 1 and my firefox is the 43 hope someone here can help me to resolve this problem....thank you

hi , recently i'm having problem on play some videos receving the error that mime type is not supported and also i can't view videos on socials like twitter , im using this site for testing http://www.quirksmode.org/html5/tests/video.html and the video i can't view is the first H.264/MP4 here a image of the error http://i.imgur.com/Vb1QJXq.jpg im on windows vista 32 bit service pack 1 and my firefox is the 43 hope someone here can help me to resolve this problem....thank you

All Replies (7)

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news on this plugin but for windows vista ?

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Firefox 47 should have Widevine plugin installed, updating your browser should be a safe bet. You can also download it here: https://en.freedownloadmanager.org/Windows-PC/Widevine-Media-Optimizer-Chrome-FREE.html Altough I'm not sure it will work, Widevine is meant to decode DRM protected content.

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Firefox loads the Widevine (and OpenH264) plugin via the URL as set via this pref:

  • media.gmp-manager.url

On Vista you may have to edit the URL and change %VERSION% to a fixed 51.0 with Firefox 52 ESR used.

Modified by cor-el

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i've already tryed firefox upgrades the 47 too but videos still not work , will that widevine fix the problem ? for that preference i don't understand where set this preference , do u mean a boolean ? if yes is set to default here some of the " media booleans " https://i.imgur.com/6uq9Aa2.jpg maybe some of them are set bad ( but i never change anything and time ago videos work... ) thanks for answers

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Ok, Firefox uses the windows built in codecs to play back H.264, so if it's not working and your config is correct in Firefox then it's a windows issue!

I have never tested any of this and am just going from memory on how FF worked on windows (I haven't used Windows at home in over 10 years) So neither of these may work...

What you need to do is download an H.264 codec pack for your windows so that Firefox can use it. But since you refuse to get the windows codec pack than the only thing I think will work is ffdshow, which you can get from here: https://www.videohelp.com/software/ffdshow (you obviously need to install the H.264 codec part of it, then most likely go into the about:config in firefox and find the ffdshow toggle and switch it to true.) Then restart the computer.

If your staying on an old version, pick an ESR release, the latest one is this: https://ftp.mozilla.org/pub/firefox/releases/45.9.0esr/

if you need an older one to work with ffdshow, then there are these: https://ftp.mozilla.org/pub/firefox/releases/38.8.0esr/


  • ONLY NEW VERSIONS*

Another option is to run an up-to date copy of Firefox and and see if it will run with FFMPEG (Which is what it uses on Linux) which you can find here: http://ffmpeg.zeranoe.com/builds/

Now after installing that you would have to goto your about:config and find the media.ffmpeg.enabled key and toggle it to "true" then restart the computer.

Modified by BeerBaroN23

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i've only "refused" to download the service pack 2 and i asked something working on my service pack 1 ( like flash player ) will the ffdshow and/or FFMPEG work on my service pack 1 and on firefox 43 ? on the page i not see the requirements , thanks for reply

maybe also know what media booleans need be set to true can help i noticed many are on false but i don't understand why if them was needed set to true why on default are set to false...

Modified by Lanselot

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