HTML5 Video

Hello-

Im creating a site using HTML5 and I have to add a video to one of the pages. I have created the page in Dreamweaver and when I test it in Dreamweaver it works fine in Safari and Firefox. But when I place it on my staging site nothing works. Is there something that I’m not doing correctly???

This is what I have:


    <video width="640" height="367" controls="controls" poster="_assets/AFPO-halfres.jpg">      <source src="_assets/AFPO-halfres.mp4" type="video/mp4" />      <source src="_assets/AFPO-halfres.ogv" type="video/ogg" />      </video> 

Thanks for your help!
Lindsae