Html5 - Mp4 Video Does Not Play in IE9

HTML5 - mp4 video does not play in IE9

Ended up using http://videojs.com/ to support all browsers.

But to get the video working in IE9 and Chrome I just added html5 doc type and used mp4:

<!DOCTYPE html>
<html>
<body>
  <video src="video.mp4" width="400" height="300" preload controls>
  </video>
</body>
</html>

HTML5 Video Not Working in IE9+10

IE only supports a limited set of codecs for video sources

IE 9+ supports h264 with mp3/aac, vp8 and vp9 are questionable, all others it does not seem to support.

MDN doc on media browser compatibility

So you will have to provide several video sources to support each browser, but not necessarily a video for each browser as some of the browsers do overlap in their support.

Providing a video with h264 aac/mp3 should play on IE, Safari, and Chrome.
While a video with Theora or VP8 should play on Firefox and Opera

mp4 video won't play in IE9 using video.js

I figured it out. It was that the request was going through the CMS I was using. The CMS can't handle requests for partial files, so it just outputs the entire thing each time. So, in my .htaccess I made it so that my mp4 files would not be routed through the CMS anymore and it started working.

IE9 not displaying mp4 video?

I still have absolutely no idea what was causing this, I spent hours digging and digging and in the end asked someone else to try in their version of IE9, for some reason it worked on their computer and not mine.

I'm not entirely sure why, I'm just putting it down to my version of IE9 being broken in some way (which is frustrating considering how much time I spent trying to sort this out!)

Html5 - Mp4 Video Does Not Play in IE9