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Unable to play any YouTube videos as "video formats not recognised".

  • 3 replies
  • 75 have this problem
  • 3 views
  • Last reply by axegirl

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Hey there,

I'm new to the forums and apologise if this question has already been solved and ask - I've had a thorough look through but seem to be experiencing a different problem to other users seeing the same error message, which reads:

"Your browser does not currently recognise any of the video formats available."

This happens for any YouTube video I try to play, and has only started happening recently. I running Windows 10 and have the most up to date versions of both my OS and Firefox. YouTube videos work fine in other browsers, but the last thing I want to do is use bloody Chrome.

The YouTube help page says my browser supports everything except MSE and WebM VP9.

Thanks in advance for your assistance!

Hey there, I'm new to the forums and apologise if this question has already been solved and ask - I've had a thorough look through but seem to be experiencing a different problem to other users seeing the same error message, which reads: "Your browser does not currently recognise any of the video formats available." This happens for any YouTube video I try to play, and has only started happening recently. I running Windows 10 and have the most up to date versions of both my OS and Firefox. YouTube videos work fine in other browsers, but the last thing I want to do is use bloody Chrome. The YouTube help page says my browser supports everything except MSE and WebM VP9. Thanks in advance for your assistance!

Chosen solution

Thank you for sharing your extension list. Please remove this extension:

YouTube™ Flash® Player

YouTube no longer provides Flash formats, and this extension may inhibit HTML5 video.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. Then cast a critical eye over the list on the right side. Any extensions that Firefox installs on its own are hidden from this page, so everything listed here is your choice (and your responsibility) to manage.

Sometimes a link will appear above a disabled/removed extension to restart Firefox before the change takes effect. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

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Chosen Solution

Thank you for sharing your extension list. Please remove this extension:

YouTube™ Flash® Player

YouTube no longer provides Flash formats, and this extension may inhibit HTML5 video.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. Then cast a critical eye over the list on the right side. Any extensions that Firefox installs on its own are hidden from this page, so everything listed here is your choice (and your responsibility) to manage.

Sometimes a link will appear above a disabled/removed extension to restart Firefox before the change takes effect. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

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Thank you jscher2000 - fixed the problem! Now I know for next time, will make sure I keep an eye on those addons.

All the best.