If you are using PowerPoint 2002/XP and above,
you can set password to protect your presentation from modification.
Go to Tools > Options > Security. Set your password there.
If you are using PowerPoint 2000 and below, this feature isn't supported.
You can though, embed your presentation into MS Word or Excel.
Check this out for more information:
"Password protect a presentation"
http://www.pptfaq.com/FAQ00038.htm

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Shawn Toh (tohlz)
Microsoft MVP PowerPoint
Site Updated: Feb 20, 2008
(Amazing PowerPoint animations, artworks, games here)
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PowerPoint Heaven - The Power to Animate
> After I have completed a Power Point Presentation, how can I prevent others
> from changing the information in the presentation?
> After I have completed a Power Point Presentation, how can I prevent others
> from changing the information in the presentation?
Setting password to protect your presentation from modification is a
good idea
there are some other suggsetion for you:
Using windows movie maker, save your presentation to jpg format and
then create a movie with the images. but the animation and sound will
lost.
Using some professional software like PPT to Video
http://www.ppt-to-dvd.com/ppt-to-video-overview.html you can sent
others a video format with animation and sound remained.