People ask me, how the files are protected from fraudulent download in detail. We have posted here serveral times before, that unpaid downloads are not possible, but here some additional info:
1.) Security by using the PayPal IPN
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If a payment reaches our system for your digital good, PayPal notifies us with a little crypted token. We take that token and ask back to PayPal, if that token is valid. So we can make sure, that the payment notification is REALLY from PayPal and not from a hacker... This is only the first step, now more checks have to follow.
2.) Additional value and currency check
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If you have sold a good for 1 USD, we have to make sure, that you have not been paid 1 YEN and hold on to your product. So we check: the product, the price and the currency. If these 3 values are correct, your digital good will be delivered, and not earlier.
This also covers the check and bank transfer payments, which can be done with PayPal to pay your goods. Only if the money reaches your PayPal account, the download is enabled.
We hope this gives you a fair overview about the security of the PayPal IPN. We strongly recommend, that you do not sell critical digital goods by using the PDT, which is only a method for statistics and double check, but can be spoofed!
Cheers,
Puzzler
