Further to Sonia's post, there are two issues in your
question.
The power point player allows for the use of the power
point viwer, but what about the content?
If you do not own the copyright of the images in your
presentation then you must have permission before you
distibute it. This includes photographs, video, graphics
and the text.
Is it flattering to see your presentations used illegally
by others or is it theft and loss of revenue?
Scotia