I have some simple code to display a video mp4 file using the html5 video tag. The code works on the production server, but not on the development servers. on those, it just shows a blank video area. The only difference that I can see is that the development (CF10) server uses Apache as a web server while the productions server uses IIS. It there something special for Apache to show the video using the video tag?
The video tag is dealt with by the browser initially. So check the path is correct firstly.
If IIS is causing the issue it would usually be to do with the MIME type not being setup. You can see if its there by going to the Mime Types section in the IIS Manager. If it isn't there then it will need adding. (.mp4 video/mp4)
I think they only added mp4 by default from Win Server 2012 onwards. If it isn't there then you will get a 404 when the media tries to load.