How can I make mp4 videos play in Firefox?
YouTube works fine. Other websites play videos, no problem. But then I'll go to a website and see a message that the video is either corrupt or is not supported. When I search for how to play mp4 in Firefox I end up at this site: http://www.jwplayer.com/blog/the-state-of-html5-firefox-now-supports-mp4/ With the huge headline Firefox Now Supports MP4. No, it ****ing doesn't! A bit frustrated, because everywhere I look for help on this, I either come across pages saying it should work, Firefox supports mp4 etc, OR forums where it's webmakers asking the question and then the solution is something wrong in their coding - which doesn't help me, the lonely end user. When I go to this suggested test site: http://techslides.com/demos/sample-videos/small.mp4 I get the error message: Video can't be played because the file is corrupt. No, it's not. I can download it and play it on WinAmp. When I go to this suggested test site: http://www.html5videoplayer.net/html5video/mp4-h-264-video-test/ I get the error: No video with supported format and MIME type found. Huh? Again, I can download and play it fine. But Firefox won't play it. Soooooo Is there a fix in the wind? Is there something I can tweak or change to make Firefox recognize and play this stuff? Is there a plugin/extension/addon that I need to download to play mp4? If this is a known problem that is going to be fixed eventually, is there something I can do as a substitute (ie a plugin for now)? Because it seems like the only alternative is to abandon Firefox and start using Chrome, which has no problem with the above-mentioned videos.
Chosen solution
you may be needing this in case you do not have support for MP4 files:
Windows Media Feature Pack for Windows 7 N and for Windows 7 KN:
- http://support.microsoft.com/kb/968211
- http://www.microsoft.com/en-us/download/details.aspx?id=16546
Also make sure that these prefs have the default value:
- media.windows-media-foundation.enabled
- media.directshow.enabled
You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.
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I have win7 home, firefox 35.0.1. Java but no other add-on/extension that matters. And it works, both your links. Try running firefox in safe mode and see if it works
What is the web site / address that does not work?
Flash Player Test Page YouTube Test Page: What video does this browser support
Running Firefox in Safe Mode and neither of the links noted above will play video; both show the same error messages quoted in my original post.
The links I posted are to test pages.
Type about:addons<enter> in the address bar to open the Add-ons Manager. Hot key; <Control>(Mac:<Command>) <Shift> A)
On the left side of the page, select Plugins. Make sure the ones you want to use are set to Ask or Allow.
Go to the web page. Once the page is loading, mouse to the address bar and Left click the icon. A window for displaying site information should come up. Select More Information. Now select Permissions. In the menu, Make sure the ones you want to use are set to Ask or Allow.
FredMcD - you are missing the point entirely. I am not having trouble with Flash Player, nor YouTube, as I stated in my original post. I cannot select the plugins I want to use to play mp4 because I do not know which ones will play it. That is essentially what I am asking: how do I make mp4 play in Firefox? Clicking for site info, I will tell you that everything there is set to Use Default. For Flash, it is set to Always and everything else is set to Ask - but nobody ever asks, so I don't know if I have the plugin I need already and it's not asking or if I need something else. And you can see all the plugins I have by clicking on Question Details, above.
If you want to know what plugin is playing the video, right click on the video when the player is loaded. If you want to choose what plugin is used, just set that plugin to Always, and the others to Ask.
Chosen Solution
you may be needing this in case you do not have support for MP4 files:
Windows Media Feature Pack for Windows 7 N and for Windows 7 KN:
- http://support.microsoft.com/kb/968211
- http://www.microsoft.com/en-us/download/details.aspx?id=16546
Also make sure that these prefs have the default value:
- media.windows-media-foundation.enabled
- media.directshow.enabled
You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.
FredMcD - if the plugin was playing the video, I wouldn't be here. I don't care what plugin plays a video, as long as the video plays. THE VIDEO IS NOT PLAYING! Therefore, I cannot find out which plugin...........................I'm too tired to keep explaining this to you.
cor-el - My COMPUTER plays mp4 just fine. It's FIREFOX that does not play it. I can download the same videos that Firefox won't play and then play them on WinAmp. Windows Media Player won't play it, but it plays in Internet Explorer and Chrome. But WAIT! Your tip about checking about:config seems to have worked. media.windows-media-foundation.enabled was set to false (bold) so I double-clicked and restarted Firefox and these test videos are working now! So yay! :D No idea how it got flipped. Thank you very much!
I'm using Firefox with 4 profiles. One of them had problem to work mp4. When I open mp4 http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 it says "Video can't be played because the file is corrupted.".
After I compare prefs.js files of both profiles I saw that "media.windows-media-foundation.enabled" was false. I opened about:config and reset "media.windows-media-foundation.enabled". After restarting Firefox http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4 has been working perfectly.