1 - It may have gotten corrupted during download , try re-downloading .
or 2 - corrupted when you uncompressed the file . I like to use "Winzip" , it does a good job .
or 3 - you may not have the correct codecs installed in your video player .
I hope this helps , need more info to know why it didn't work .
Try the " Tech Help " link at the top of the page .
Good luck
Us Yanks here in the states are celebrating Independance Day .
Cheers to all , have a great day !!
Harper