Set Windows Media properties
You can edit properties that are unique to Microsoft Windows Media files (*.asf, *.wm, *wma, *wmv, *.wmd, and others) and some common HTML properties in the Windows Media Player Properties dialog box. The properties that are available vary depending on the version of the Windows Media player that is installed on your computer. For more information, see the MSDN library online.
You need to have Windows Media Player installed on your computer to play Windows Media files in your web pages in Design view and to edit the properties that are unique to the format.
For information about inserting and editing Windows Media files, see Insert and edit Flash (.swf), Windows Media, and other media files.