My HTML5 Video Stack will not play

Video hosting is tricky, and it's hard to get right first time. Here are a few simple troubleshooting steps to get things running smoothly.

Check your server settings

To play correctly in Firefox, your server needs to be sending video files using the correct mimetype. To ensure that your server is playing nicely, create a file called .htaccess in the root of your site, and add the following lines:
AddType video/ogg .ogv
AddType video/mp4 .mp4
AddType video/webm .webm

If you're not using Apache to serve your files, then the above settings have to be altered slightly. Instructions on how to set up mimetypes for windows servers can be found here for IIS6 and IIS7.

Check your video encoding

Some MP4 & OGG files are a bit weird, and won't play properly on the web. You can generally fix this by re-encoding your video or audio with Miro video converter.

Check out our FAQ on this with HTML5 Audio... HTML5 Audio Create OGG Files for HTML5 Audio Support in Firefox

Check your Flash security settings

If you're having problems getting your videos to work locally, make sure you go to the Flash Security Settings page and add your working directory.