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MP4 Video is not playing in Firefox 35.0.1

  • 8 replies
  • 11 have this problem
  • 10 views
  • Last reply by FredMcD

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Some of my MP4 videos are not playing in Firefox. They worked fine last week. Now I get the "Video can't be played because the file is corrupt" message. The video works fine in IE, Chrome, Opera, Safari

Some of my MP4 videos are not playing in Firefox. They worked fine last week. Now I get the "Video can't be played because the file is corrupt" message. The video works fine in IE, Chrome, Opera, Safari

Chosen solution

I'm using Firefox with 4 profiles. One of them had problem to work mp4. When I open mp4 http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 it says "Video can't be played because the file is corrupted.".

After I compare prefs.js files of both profiles I saw that "media.windows-media-foundation.enabled" was false. I opened about:config and reset "media.windows-media-foundation.enabled". After restarting Firefox http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 has been working perfectly.

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All Replies (8)

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No problems here with both those MP4 files in the built-in HTML5 media player.

Make sure that your security software isn't causing this problem. Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

I see that sudogo has created a new thread, so lets continue there.

Modified by cor-el

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I'm able to reproduce the issue with the MP4 gdws1_15.mp4. See bug https://bugzilla.mozilla.org/show_bug.cgi?id=1133504

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If you have problems with current Shockwave Flash plugin versions then check this:

  • see if there are updates for your graphics drive drivers

https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

  • disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later)

https://forums.adobe.com/message/4468493#TemporaryWorkaround

  • disable hardware acceleration in the Flash plugin

https://forums.adobe.com/thread/891337 See also:

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Read the bug report, it's a bug in Firefox and it will be fixed in FF37+.

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Chosen Solution

I'm using Firefox with 4 profiles. One of them had problem to work mp4. When I open mp4 http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 it says "Video can't be played because the file is corrupted.".

After I compare prefs.js files of both profiles I saw that "media.windows-media-foundation.enabled" was false. I opened about:config and reset "media.windows-media-foundation.enabled". After restarting Firefox http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 has been working perfectly.

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Good to hear, Well Done.