New to HTML5

[Dave]

I've recently purchased 2 books on HTML5. I've gone through the
sections on video and have tried using the <video> tag...with no
luck. I've tried using 3 different mp4 files and all 3 come up unable
to use. I've tried the tag on an HTML and ASPX page (playing devils
advocate) and still no luck. Can anyone tell me what I'm doing wrong
here? Did I miss something?

<video preload="auto" controls autoplay width="640"
height="480">
<source src="video/Test.mp4" type='video/mp4;
codecs="avc1.42E01E, mp4a.40.2"' />
TEST
</video>

[Heff (VideoJS)]

Got a link to a live example? You sure the video/Test.mp4 is the
correct URL (tried a full url w/ http?)? Using a browser that can play
an mp4 file, like Chrome, Safari, or IE version 9?