Convert WMV to MPEG

I’m getting an error using Super DVD Creator 8 when I try to convert WMV file to MPEG.

The error message is as follows....

Not supported media format, You need to install some codec. RenderFile (wFile)

Any ideas?? I have the Windows Media 9 runtime files installed and all codecs that I know of. If anyone can help please do so. Thanks in advance.

Advanced X Video Converter
http://www.aoamedia.com

Hope it helps.

“Convert, Join, and Split video files among AVI (DivX, XviD, MPEG-4...), MPEG (MPEG-1, MPEG-2), WMV/ASF, VCD (.dat), SVCD, DVD formats. Extract sound track and images from videos. "

Bonjour j’aimerais télécharger le codes XviD MPEG-4 commment faire?
merci d’avance