Windows Media Format 11 Runtime is required to decode/encode Windows Media Video (WMV, WM) and Windows Media Audio (WMA) files without installing Windows Media Player 11.

Windows Media Audio (.wma) :
Windows Media Audio (.wma) files are Advanced Systems Format (.asf) files that include audio that is compressed with the Windows Media Audio (WMA) codec. By using a separate extension, users can install multiple players on their computer and associate certain players with the .wma extension for playback of audio-only sources.

Windows Media Video (.wmv, .wm) :
Windows Media Video (.wmv) files are Advanced Systems Format (.asf) files that include audio, video, or both compressed with Windows Media Audio (WMA) and Windows Media Video (WMV) codecs. By using a separate extension, you can install multiple players on your computer and associate certain players with the .wmv extension for playback of audio and video sources.

• Important Note: Windows Media Format 11 Runtime requires Windows XP Service Pack 2.

Windows Media Format 11 Runtime

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