Wenn man die HTML 5 MIME Types per web.config definieren will geht das ganz einfach so:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.webServer>
<staticContent>
<!-- HTML 5 Video Mime Types-->
<mimeMap mimeType="video/ogg" fileExtension=".ogm" />
<mimeMap mimeType="video/ogg" fileExtension=".ogv" />
<mimeMap mimeType="video/ogg" fileExtension=".ogg" />
<mimeMap mimeType="video/webm" fileExtension=".webm" />
<mimeMap mimeType="audio/webm" fileExtension=".weba" />
<mimeMap mimeType="video/mp4" fileExtension=".mp4" />
<mimeMap mimeType="video/x-m4v" fileExtension=".m4v" />
</staticContent>
</system.webServer>
</configuration>