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)
http://pptheaven.mvps.org
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