Why does Safari not recognize any of the video formats available?

Make sure your Mac's software is up to date. Open the App Store then select Updates from the menu.

And go to Safari > Preferences then select the Security tab. Make sure Allow Plug-ins is selected.

If you view video content on YouTube, make sure Flash is up today. Open System Preferences > Flash Player then select the Updates tab then click: Check for Update.

What OS version and Safari version are you using?

I'm using OS X 10.11.6 and just today installed Safari 10.0.1 as recommended by the App Store. Now I can't view any HTML5 or other video formats. Everything on YouTube or other sites using HTML5 gives me the same message as mentioned in the initial post in this thread: "Your browser does not currently recognize any of the video formats available." Following the suggestions made here, I updated Adobe Flash Player and checked that in Plug-In Settings. Still no luck. Not having access to any YouTube videos or other HTML5 videos anywhere else on the web is disconcerting, to say the least. Had no problems when I was using earlier version of Safari. Until this is fixed in Safari 10, can I go back and use the earlier version via Time Machine or will that screw everything up even more? Help! Please!

Send Apple feedback. They won't answer, but at least will know there is a problem or a suggestion for change. If enough people send feedback, it may get the problem/suggested change solved sooner.

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yazzthe1st wrote:

Hasn’t most everyone gone over to HTML 5?

Most have, but many prefer to reserve that option for mobile devices. There's workaround for that: in Safari>Preferences>Advanced check the bottom most option (Developer menu). You'll get a new menu bar item, click on that, select User Agent and chose one of the iOS items (e.g. iPhone). Reload the page, and in many cases your video works – without Flash. Just like that.

Personally I've uninstalled Flash earlier this year, and haven't had any trouble with video content in Safari (or any other browser for that matter).

Thanks. I finally figured out what was wrong. I've been using a Safari Extension, ClickToFlash, which I originally got from the App Store, but which is no longer supported or offered there. It's worked fine up until now, even though it's no longer supported. Apparently Safari 10 finally killed it. When I turn ClickToFlash OFF, everything works fine, with or without FLASH turned on. So in my case, I guess that was it. I plan to uninstall ClickToFlash, since it now appears both useless and creates problems. Thanks to all for the help.

Thank you. I finally decided to try and understand why Youtube would not play videos on my new iMac. I have not installed Flash on purpose but I did not delete ClickToFlash thinking that it wouldn't matter. Removing ClickToFlash has solved my problem and I am now able to see Youtube videos again. Still no Adobe Flash.