The Windows Media Player 11 UPnP AV server does not support all the same files and codecs as the Media Player.
The Windows media player 11 UPnP AV server supports:
• Music files, such as Windows Media Audio (.wma), MP3 (.mp3), and WAV (.wav) files. Note that audio CDs that are inserted into your computer can't be shared.
• Video files, such as Windows Media Video (.wmv), AVI (.avi), MPEG-1 (.mpeg, .mpg), and MPEG-2 (.mpeg, .mpg) files. Note that DVD-Video discs that are inserted into your computer can't be shared.
• Picture files, such as JPEG (.jpeg, .jpg), portable network graphics (.png), and Windows Media Photo (.wpd) files.
• Playlists, such as Windows Media playlist (.wpl) and MP3 playlist (.m3u) files.