Take a look here for help:
http://www.pptfaq.com/FAQ00266.htm

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Sandy Johnson
Microsoft Certified Office Specialist (MOS PowerPoint)
> I am trying to add a clip to my presentation and I get an error message, is
> there a way around this?
Olivia
Visit
http://www.playsforcertain.com
I'm pretty sure the 'free trial' will make your mp4 video play just fine.
Cheers
TAJ Simmons
microsoft powerpoint mvp
awesome - powerpoint backgrounds,
http://www.awesomebackgrounds.com
free powerpoint templates, tutorials, hints, tips and more...
>I am trying to add a clip to my presentation and I get an error message, is
> there a way around this?