After adding a digital product, from the administrative control panel do the following:

• Hover your mouse over “Subscriptions” and click on “Add a Product”
• Select “Type” as “Single Purchase”
• Input a generic name and description for this product.
• Input the price of the digital product.
• Scroll down to the section entitled “Digital Product Access” and tick the checkbox next to the digital product that you wish to charge users for.
• Click on “Add Product”

The screen will reload and a list of products will appear with the new product included. Find the product ID and use this to create a payment link for the digital product. You can also allow users to purchase this product from the cart catalog:

http://www.yoursite.com/ppSD2/catalog.php