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Firefox 49 error "This browser does not support video playback" playing mp4 videos in Twitter in Win 8.1 with Flash Player 23.0.0.162

  • 22 replies
  • 13 have this problem
  • 470 views
  • Last reply by 1artworkz

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About a month and a half ago MP4 videos in Twitter 29 played fine. Then I updated to the latest version of Adobe Flash player on both my Win 8.1 and old XP computers. That is when I started getting "This browser does not support video playback" error when trying to play a mp4 video in Twitter. I ran Firefox in Safemode ... no change. I removed all addons ... no change. All Plugins are Ask to Activate or Always Activated. I uninstalled Firefox and Flash player and reinstalled .. no change. The videos work fine in MS IE II and Chrome 53.0.2785.116 m. H264 Codec is installed. YouTube videos play fine.

About a month and a half ago MP4 videos in Twitter 29 played fine. Then I updated to the latest version of Adobe Flash player on both my Win 8.1 and old XP computers. That is when I started getting "This browser does not support video playback" error when trying to play a mp4 video in Twitter. I ran Firefox in Safemode ... no change. I removed all addons ... no change. All Plugins are Ask to Activate or Always Activated. I uninstalled Firefox and Flash player and reinstalled .. no change. The videos work fine in MS IE II and Chrome 53.0.2785.116 m. H264 Codec is installed. YouTube videos play fine.

Chosen solution

SOLVED: I was wrong. This problem has nothing to do with the way Firefox handles videos in Twitter. It has to do with how Windows handles videos. I initially ran a System Restore which installs a fresh copy of Win 8. I installed A fresh copy of Firefox 43 and did not get the error. I then restored my system using a back up image. I then tried removing every possible file and folder that was installed by Firefox on my computer and installed several different versions of Firefox and still got the same error. Back in June 2016 I turned off Automatic Updates because of the annoying nag to upgrade to Win 10 and totally forgot about turning it back. After turning Auto Backup on and installing all the upgrades, I no longer get the error message. I am now running Firefox 49 with the New Tab URL addon which fixed the New Tab feature I did not like. I want to thank jscher2000 for his diligent help and others that sent me helpful suggestions. I still have this problem on my old XP computer but I'm not going to attempt to fix it as I don't use it much for accessing the Internet.

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Just so you know, if you want to have a customized new tab URL, you can use the Custom New Tab add-on or an equivalent.

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Chosen Solution

SOLVED: I was wrong. This problem has nothing to do with the way Firefox handles videos in Twitter. It has to do with how Windows handles videos. I initially ran a System Restore which installs a fresh copy of Win 8. I installed A fresh copy of Firefox 43 and did not get the error. I then restored my system using a back up image. I then tried removing every possible file and folder that was installed by Firefox on my computer and installed several different versions of Firefox and still got the same error. Back in June 2016 I turned off Automatic Updates because of the annoying nag to upgrade to Win 10 and totally forgot about turning it back. After turning Auto Backup on and installing all the upgrades, I no longer get the error message. I am now running Firefox 49 with the New Tab URL addon which fixed the New Tab feature I did not like. I want to thank jscher2000 for his diligent help and others that sent me helpful suggestions. I still have this problem on my old XP computer but I'm not going to attempt to fix it as I don't use it much for accessing the Internet.

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