Playing MP4 videos from Server on IE9

I am trying to play .mp4 videos from Server on my HTML5 web page, but it's not showing the video.

I have the MIME type as video/mp4 on the server. I have checked it on Developer tool , its giving me error code 4 which is 

Encoding not supported by IE9. 

I have seen .mp4 videos hosted on other webpages playing fine.

Please provide any assistance if possible.

Code is like this

<video width="300" height="162" ><source src=".....video.mp4"  type="video/mp4"></video>

Thanx in advance.