Hi vipichi,
There are probably many ways to do this but I guess you want to keep it as simple as possible. Here is one way to do it. Each E-book has an orderID and that orderID goes into the order DB when someone heads to PP. Once they return etc and the IPN validates their payment you can allow them to download it by making it a link in there account orders page (if you have one). Usually a customer can login and see what they have ordered and click on the order link to reveal the product - instead of viewing it they could download it. You provide
security for your Ebooks this way due to the fact that the ebook will only download if the link is from the orders page. That stops anyone getting the link and downloading the book. The order can perish after a period of time or number of downloads. Confused? let me know if that makes any sense.
Cheers,
Mark
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