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Cannot play JWPlayer mp4 videos - "error loading media, file could not be played" in MS Windows 7 Firefox. Works on Firefox for mac.

  • 1 reply
  • 23 have this problem
  • 15 views
  • Last reply by cor-el

Kelly.w
Kelly.w
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We use mp4 / mv4 type videos. These videos are viewed through a JWPlayer playlist. They work fine using Firefox browser on a MAC, however on MS Windows 7, I get "Error loading media, file could not be played". They also work fine from MS Windows 7 using IE and CHROME browsers. Any idea what might be causing the problem when trying to play them from the Firefox browser on a Windows platform?

I have already tried uninstalling Firefox, deleting my profile and re-installing the latest version.

I logged a support problem with JWPlayer and they indicated that it ma be a browser specific related issue with html5?

Thanks for you help!

We use mp4 / mv4 type videos. These videos are viewed through a JWPlayer playlist. They work fine using Firefox browser on a MAC, however on MS Windows 7, I get "Error loading media, file could not be played". They also work fine from MS Windows 7 using IE and CHROME browsers. Any idea what might be causing the problem when trying to play them from the Firefox browser on a Windows platform? I have already tried uninstalling Firefox, deleting my profile and re-installing the latest version. I logged a support problem with JWPlayer and they indicated that it ma be a browser specific related issue with html5? Thanks for you help!

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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I would assume an issue with the HTML5 media player.

If those aren't working on Windows then it is possible that the proper codecs aren't installed.

You can try to disable the HTML5 media player and make Firefox use the Flash plugin.

You can do this by setting these two prefs to false on the about:config page:

  • media.windows-media-foundation.enabled
  • media.directshow.enabled

See also: Windows Media Feature Pack for Windows 7 N and for Windows 7 KN: