The purpose of this article is to educate PayPal developers on how to make purchased downloads secure using the PayPal payment system, the Instant Payment Notification (IPN) feature, and a dynamic server page technology (ASP in this example). Reference URL:
www.superfreaker.com/paypal/softserve/
This tutorial is intended for PHP programmers of all levels, who wish to add Paypal functionality to their website. The programmer needs only a PHP enabled website and Paypal account.
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