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Firefox (Windows 7) cannot play some mp4 videos

  • 2 replies
  • 2 have this problem
  • Last reply by ellaryk

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Firefox 42 for Windows 7 cannot play some mp4 videos, for example: (either opening directly or embedded in a webpage) Firefox displays the error message: Video can't be played because the file is corrupt. Tested on different machines. The video is encoded in H264 and AAC, it works under Chrome and Firefox for Linux.

(The option "" is no longer available in about:config),

All Replies (2)

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My Firefox would not play the file. But when I opened the link in Win IE, it downloaded. It played fine after the download.

I've called the big guys to help you. Good luck.

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I also have this problem using Win10 and Firefox 43.0.2. Works fine in Chrome and Edge. Tried uninstalling and reinstalling Adobe Flash per instructions I found Googling the problem but it didn't fix it.