Windows Media Player 11 SDK Compatibility Issues
Web pages opened by the HTMLView feature are displayed using an embedded instance of Microsoft Internet Explorer. No Netscape compatibility is required for HTMLView content.
No HTMLView support in earlier versions of Windows Media Player
Currently, only Windows Media Player 9 Series or later supports the HTMLView feature. Earlier versions of the Player and versions created for other platforms ignore the HTMLView parameter when parsing an .asx file. When this happens, the digital media content plays as expected, but the Web-based content is not displayed in the Now Playing feature.