PDF is probably the best solution for emailing but another way to protect the
content of your presentations try the following:
New blank presentation - insert object, create from file and then browse to
the .ppt you want to use. You will need to size the image that appears to
fit the screen. Then save as a .pps with password protection to edit. Works
a treat.
I think this was originally a suggestion from either Glenna Shaw or Sonia
Coleman, definitely one of the MVPs. Whoever it was my thanks a hundred
times over and hope you don't mind me spreading the word.
David