SMIL file not showing video image with real player

[Bimal]

Hi Everybody,
                   I have a strange problem with smil file .
                   I had created a smil file which call a video file i.e .wmv file for playing the video,
                   but it show me only audio while playing the same smil file with real player .
                 
                   I have real player 11 (free version) install which support all the major media format.
                   I even select all media format from preferences in real player .
                   
                   If I paly the same wmv  file with real player directly it is playing .
                   I m not able to figure out which one having problem real player or SMIL file .

                  Can any body help me out .

Regards,
Bimal