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Most Youtube videos have an error

  • 3 replies
  • 6 have this problem
  • 1 view
  • Last reply by Knaifhogg

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This started a few days ago, I have no idea how it started. Basically very many Youtube videos don't start in Firefox. They work fine in Chrome (although they don't seem to load instantly, takes a while to start). Here's a screenshot: http://i.imgur.com/z5XP0zU.png

What I've tried:

Reinstall Firefox Reinstall Flash Clear cache in both Firefox and Flash New profile in Firefox Change to HTML5 on Youtube (and turn off Flash in plug-ins)

The Youtube HTML5 page (https://www.youtube.com/html5) looks like this http://i.imgur.com/KlOSgOR.png. In Chrome it's all green.

Please help.

This started a few days ago, I have no idea how it started. Basically very many Youtube videos don't start in Firefox. They work fine in Chrome (although they don't seem to load instantly, takes a while to start). Here's a screenshot: http://i.imgur.com/z5XP0zU.png What I've tried: Reinstall Firefox Reinstall Flash Clear cache in both Firefox and Flash New profile in Firefox Change to HTML5 on Youtube (and turn off Flash in plug-ins) The Youtube HTML5 page (https://www.youtube.com/html5) looks like this http://i.imgur.com/KlOSgOR.png. In Chrome it's all green. Please help.

Chosen solution

I seem to have solved the problem. I had to manually go remove all Java versions I had and install the newest one. I believe the auto-removal of older versions in the applet when you install didn't work, so I had many versions installed at the same time, and I guess Firefox didn't like that.

Basically all I had to do was go to Programs and Features, remove everything Java related and download it again.

Read this answer in context 👍 0

All Replies (3)

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To see "more green" you can enable Media Source Extensions support in Firefox by setting this pref to true on the about:config page.

  • media.mediasource.enabled = true

See:


Did you clear the YouTube cookies as well?

You may also have to clear the Flash local storage.

  • Windows Control Panel > Flash Player > Storage: Local Storage Settings
    • Remove a specific domain: Local Storage Settings by site
    • Remove all domains: Delete All and Delete Data

Flash Website Storage Settings panel:

Global Storage Settings Panel:

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If I set media.mediasource.enabled = true, Youtube stops working completely if I have enabled html5. There's a never-ending loading screen on the flash player. The other combinations of html5 on and off and this true or false appear to be the same (error).

Yes I have cleared both cookies and cache, browser and flash.

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Chosen Solution

I seem to have solved the problem. I had to manually go remove all Java versions I had and install the newest one. I believe the auto-removal of older versions in the applet when you install didn't work, so I had many versions installed at the same time, and I guess Firefox didn't like that.

Basically all I had to do was go to Programs and Features, remove everything Java related and download it again.