how to set up iis mime settings for .mp4

Question

i want to play mp4 videos on iis(v6.0) webserver, i have setting for extentions for .mp4, and also set up mime setting like this: ---- .mp4 ---- video/mp4

But can not play the file in quick time or flash players on my webpage...

I also placed the below link in address bar but : cann't display page came.. http://www.mywebsite.com/folder/video_1.mp4 (path is correct)