avi clip does not play

I inserted a .avi video clip into my powerpoint
presentation. It does not play the clip on my laptop
although it does play it on many other desktops. I can
hear the audio from the clip but this is the message I get
on the screen as the audio is playing on:
video not available, cannot find 'vids:mpg4' decompressor

Please help. Thanks,

 

thank you for that, I've been looking to get mine to run for ages.Thanks a million