How Does It Work?

By using our Pay-Pal IPN software, your customers will purchase your product through Pay-Pal. (Note: Pay-Pal does not require customers to setup an account before buying, they only need a credit card.) Once they have completed their secure transaction with Pay-Pal, it will send info to the "notify.cgi" script located on your server. This script will check the info that Pay-Pal has sent, make sure it is a valid transaction. This script will create a transaction file for that customer on your server.

Pay-Pal will also redirect that same customer back to your website, pointing them to the "download.cgi". This script checks that transaction file to see if the transaction has been completed. If it has, it lets the user download their purchase. If it has not been completed, it will notify them of the reason and not let them download until it has been completed. (Pay-Pal will send info to the "notify.cgi" script again when the transaction status has changed.)

You have to setup your store with the Pay-Pal "Buy Now" buttons, which will contain a product ID for that product. Each product will have its own ID. The IDs will be listed in the "products.txt" file, along with the name and location of the product. If the customers transaction was completed, the "download.cgi" script reads the "products.txt" file and sends them the download. Your customers should never see the real location to the product. They will only see something like this:

http://www.youdomain.com/cgi-bin/download.cgi?action=get_file&id=22&txn_id=1K1R7M0RFQDM

But just to be more secure, it’s a good idea to place all of your products in a directory located outside of your public web, or if you do not have access to that, a password protected directory. Also you can set a limit on the number of times a customer can download their purchase. Once they reach their limit, the script will notify them of that and not let them download anymore.

Lastly, you can use the "admin.cgi" script to access all of the transactions, where you can edit and delete them, and even create new ones bypassing Pay-Pal. It will also track the number of times each customer has attempted downloaded their purchase, as well as the number of times each product has really been downloaded. If you have a new version of a product and you want your customers to be able to download for free, you can send an email to those customers that have purchased that product telling about the update. The "admin.cgi" script will then reset their download limit, letting them download it again for free. (You will also have to reflect the updated file name in the "products.txt" file.)