Hi, I see a bunch of errors in your Video Card info that was sent. I suggest re-install your video drivers/software suite https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

Remember to re-boot the cpu after. If that fixes all the errors in the drivers, great.

Please Update to Flash Player Version: 26.0.0.137 https://get.adobe.com/flashplayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

Please let us know if this solved your issue or if need further assistance.

I re-installed video drivers and updated the Flash Player but still dosent play. I can play pre-recorded videos on Youtube and elswhere but not live video.

I have played live Youtube video but with an older version of Firefox. Have also played HTML5 video before installing the flash ad on. Firefox will also will not play embedded videos on Twitter unless it's a Youtube linked video. I think HTML5 video is the problem.

EDIT: Looks like it's H.264 video that won't play - on test websites HTML5 video played fine, H.264 did not. Any suggestions?

Firefox relies on built-in OS support to play (MP4) media files via the HTML5 media player. On the Windows XP platform you do not have native support for playing MP4 files with the HTML5 media player.

You can try if the solution posted here to add support for playing MP4 files works for you.

• http://www.msfn.org/board/topic/175591-enable-mp4-h264-aac-html5-video-in-firefox-on-windows-xp-without-flash/

Thanks for the link, but all that is too technical for me.

seems i have this problem too so there is an solution for windows vista too http://www.msfn.org/board/topic/175591-enable-mp4-h264-aac-html5-video-in-firefox-on-windows-xp-without-flash/ here only talk about windows xp...thanks

anyone know if a solution exist for vista too please ? thanks

Lanselot said

anyone know if a solution exist for vista too please ? thanks

For Vista, you need to install or update the Microsoft Media Foundation. What you need to get there is in your thread here: https://support.mozilla.org/questions/1169212

I'm having similar problems with recently uploaded youtube videos. I have to wait hours or an entire day before any channel's most recent video will play. I can sometimes see a still frame if I hover the cursor arrow over the progress bar but the video just doesn't play. Some channels videos will play 15 hrs after upload, others 5 to 9hrs, it varies per channel. I get the same results whether I'm logged in or not. Otherwise their entire library of videos play just fine without any stalls or problems. I just have to wait at least one day and half to view their newest. This problem began only about a week ago.

Hi skylx18, If you run Windows XP, this doesn't surprise me. If the video was uploaded in H.264/MP4 format, Firefox on Windows XP lacks the Media Foundation code used to decode MPEG video. My theory about the delay is that Google generates new video formats over time in the background. Eventually it creates formats that Firefox can play on Windows XP. Similar thread: https://support.mozilla.org/questions/1169332 (long messy discussion).

If you run Windows Vista or higher, please check this article: Fix video and audio problems on Firefox for Windows N editions.

I have this problem with windows 10. What is going on? I've been with Firefox a long time but I hate changes that degrade my computer performance. Some one has to know what is causing this, yet no answer readily available!!! Maybe time to leave? Mike

Hi Mike, Firefox doesn't have the same limitations on Windows 10 that it has on Windows XP. Please start here: Fix video and audio problems on Firefox for Windows N editions.

I have Windows 10 so I went to the media updates and there were two files and I tried both and was told "this update does not apply to my computer". The result is that my problem remains. Until Firefox gets its act together Im using MS Edge.

Hi Mike, if you decide you want to troubleshoot this further, please start a new thread so we can keep the Windows XP issue separate from other versions.

https://support.mozilla.org/questions/new/desktop/fix-problems

Scroll down past the article suggestions to continue with the form.

Also, please test in Firefox's Safe Mode and report on the results since you will surely get that suggestion anyway. In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Thanks, Mike