HUH?? WHAT you talking about silly boy?? Your video of what won't play on where?? What kind of file are you meaning....an mp3 maybe.....Your question is too ambiguous to answer with any degree of certainty.
Try downloading the DivX Player with the codecs.
Make sure you have all the updates applied to your operating system.
Make sure you have all the updates for your player.
Try using all available, popular players....RealPlayer Basic, Quick Time, Windows Media Player, AVI preview Player......one may work with the file you are using where another one won't.
Players can be found at
www.download.com.