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No H.264/mp4 video playback (FF57x64 Win10Home)

  • 4 replies
  • 8 have this problem
  • 2 views
  • Last reply by kkkkzk

kkkkzk
kkkkzk
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I can't play videos on Facebook.

I am using Firefox 57.0.4 x64.

Firefox console says:

No decoders: video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401f", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2"

Youtube html5 test says no H.264 and no MSE & H.264.

I'm on Windows 10 Home WITHOUT any "N"-s, so that Windows Media Feature Pack would be missing.

I have tried all solutions presented to similar problems. None of them worked.

How can I make it work?

I can't play videos on Facebook. I am using Firefox 57.0.4 x64. Firefox console says: No decoders: video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401e", video/mp4; codecs="avc1.4d401f", video/mp4; codecs="avc1.4d401f", audio/mp4; codecs="mp4a.40.5", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.4D401E mp4a.40.2", video/mp4; codecs="avc1.4D401F mp4a.40.2", video/mp4; codecs="avc1.640032 mp4a.40.2", video/mp4; codecs="avc1.640033 mp4a.40.2" Youtube html5 test says no H.264 and no MSE & H.264. I'm on Windows 10 Home WITHOUT any "N"-s, so that Windows Media Feature Pack would be missing. I have tried all solutions presented to similar problems. None of them worked. How can I make it work?

Chosen solution

None of these did work either. I have wasted so much time on troubleshooting this it turned out that formatting C: was a faster solution :(.

Anyway, thanks for your help!

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All Replies (4)

James
James
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https://support.mozilla.org/en-US/kb/fix-video-audio-problems-firefox-windows

kkkkzk
kkkkzk Question owner
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Thanks for the answer.

Maybe I've constructed that sentence in a weird way, but what I meant was that it is a regular Windows version, with the Windows Media Features installed, so that solution you suggested won't do anything.

James
James
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  • Top 10 Contributor
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Some people have had issues with HTML5 player on Youtube and other sites due to extensions like Youtube Flash or force HTML5 player or such installed in Firefox.

Type about:config with a : in Location (address) bar and make sure none of the below Preferences are user set, if any are then double-click them to restore the default value of true

  • media.mediasource.enabled
  • media.mediasource.mp4.enabled
  • media.mp4.enabled
  • media.ogg.enabled
  • media.webm.enabled

After this try the https://www.youtube.com/html5 page again.

Modified by James

kkkkzk
kkkkzk Question owner
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Chosen Solution

None of these did work either. I have wasted so much time on troubleshooting this it turned out that formatting C: was a faster solution :(.

Anyway, thanks for your help!