This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Unable to Playback Video

  • 4 replies
  • 0 have this problem
  • 27 views
  • Last reply by James

more options

I took a video on a Google Pixel 7 mobile. It plays back on the Android cell properly. I can log into my Google Photos via my Windows 10 PC and the video will play back properly. I also downloaded the video file (MP4) to be saved directly in my Videos folder on my Windows 10 PC. When I try to play the video by clicking / opening the downloaded file on my PC I get an error message. See that message attached. It is prompting me to "download a new codec". Why? In my Firefox browser I currently have the Open H264 Video Codec by Cisco plugin enabled. Why is the Cisco plugin not sufficient? Is the Cisco plugin being updated? Does Firefox browser need to be updated? Is Is Firefox working on a fix?

I took a video on a Google Pixel 7 mobile. It plays back on the Android cell properly. I can log into my Google Photos via my Windows 10 PC and the video will play back properly. I also downloaded the video file (MP4) to be saved directly in my Videos folder on my Windows 10 PC. When I try to play the video by clicking / opening the downloaded file on my PC I get an error message. See that message attached. It is prompting me to "download a new codec". Why? In my Firefox browser I currently have the Open H264 Video Codec by Cisco plugin enabled. Why is the Cisco plugin not sufficient? Is the Cisco plugin being updated? Does Firefox browser need to be updated? Is Is Firefox working on a fix?
Attached screenshots

All Replies (4)

more options

What the OpenH264 Plugin is used for https://support.mozilla.org/en-US/kb/open-h264-plugin-firefox

If you are just trying to play a video file on Windows then you may need a media player like say VLC https://www.videolan.org/

Also if you are not located in say Canada or USA then you may have a N or KN edition of Windows 10. https://support.mozilla.org/en-US/kb/fix-video-audio-problems-firefox-windows

more options

Thanks James for your reply. Your comments made me recall something I should have posted originally. When I opened the video file on Windows, the "app" that starts "automatically" is Movies & TV (from Microsoft). I also tried playing the file using Windows Media Player, but that also did not allow the playback. I am located in Canada and/or USA depending upon my travel. I understand Open H264 is for streaming. So, why is the Movies & TV app telling me I need a new codec, as per image originally posted? PS. I have not yet tried videolan

more options

The HEVC codec is H265 which requires a license. Go to about:support in the address bar and check the "Codec Support Information" section. Your GPU may have a license for HEVC hardware decoding but not software decoding, check that you have hardware acceleration enabled. To use it you will need to set media.wmf.hevc.enabled to true in about:config then restart the browser.

more options

VLC can play HEVC, just maybe not 4k smoothly. You could also try the "MPV .net" media player.