If your son opened an email and then clicked Save, it would be in your
temporary internet folder. To fnd this folder, open an email with a PPT
attachment and select Save As. Click the down arrow in the Save In box to
find the location. For example, for me it's C>Documents and Settings > xxxID
local settings > temporary internet. And that's where you can find the
document. Location might be different for you but the process is the same.