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.

Avatar for Username

ค้นหาฝ่ายสนับสนุน

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.

เรียนรู้เพิ่มเติม

หัวข้อนี้ถูกเก็บถาวรแล้ว โปรดถามคำถามใหม่หากคุณต้องการความช่วยเหลือ

Cannot play mp4 files

  • 5 การตอบกลับ
  • 2 คนมีปัญหานี้
  • 20 ครั้งที่ดู
  • ตอบกลับล่าสุดโดย FredMcD

chuck1899
chuck1899
more options

On Windows Vista, firefox 38.0.5 cannot play mp4 files. Both MPC-HC and Windows Media Player can play mp4 files. I have ffdshow installed.

These are enabled: 

   media.windows-media-foundation.enabled
   media.directshow.enabled

Results from https://www.youtube.com/html5 show:

Disabled: H.264, MSE & H.264, MSE & WebM VP9

Enabled: HTMLVideoElement, Media Source Extensions, WebM VP8

Youtube videos are also locked at 360p using the html5 player.

OGG / WebM files play fine.

On Windows Vista, firefox 38.0.5 cannot play mp4 files. Both MPC-HC and Windows Media Player can play mp4 files. I have ffdshow installed. These are enabled: media.windows-media-foundation.enabled media.directshow.enabled Results from https://www.youtube.com/html5 show: Disabled: H.264, MSE & H.264, MSE & WebM VP9 Enabled: HTMLVideoElement, Media Source Extensions, WebM VP8 Youtube videos are also locked at 360p using the html5 player. OGG / WebM files play fine.

เปลี่ยนแปลงโดย chuck1899 เมื่อ

การตอบกลับทั้งหมด (5)

chuck1899
chuck1899 เจ้าของคำถาม
more options

Can anyone help?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

You can check these media prefs on the about:config page:

  • media.windows-media-foundation.enabled
  • media.directshow.enabled
chuck1899
chuck1899 เจ้าของคำถาม
more options

They are both enabled.

Refresh Firefox - reset add-ons and settings Refreshing Firefox didn't seem to do anything either.

เปลี่ยนแปลงโดย chuck1899 เมื่อ

chuck1899
chuck1899 เจ้าของคำถาม
more options

It's been a month and even with Firefox 40.0.3 it still doesn't work.

Why?

FredMcD
FredMcD
more options

Sometimes, messages get lost from inactivity. Sorry.

check this:

  • see if there are updates for your graphics drive drivers

https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

  • disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later)

https://forums.adobe.com/message/4468493#TemporaryWorkaround

  • disable hardware acceleration in the Flash plugin

https://forums.adobe.com/thread/891337 See also: