After a successful purchase Paypal calls Linklok which will then verify the transaction (using the Paypal IPN system). If the transaction is verified Linklok will then display the download links for your products and also email them to the purchaser. These links do not show the true location of the file on your server so there is no way to bypass Linklok. Links can be set to expire between 1 minute and several years later if required (or never expire).

Features:
- Simple to install.
- Uses PHP.
- Does not require MySQL or other database system.
- Does not require cookies to be enabled.
- Works with Paypal's Buy Now and Add to Cart buttons.
- Displays download page and sends email to purchaser with secure download links.
- Will create download links only if called from Paypal.
- Links can be set to expire after fixed time period.
- Links can be locked to buyers IP address.
- Nobody ever knows the actual server location of the download file.
- Supports unlimited products.
- Supports multiple products in one order.
- Supports multiple files per product.
- Works with auction (eBay) products.
- Supports multiple currencies.
- eCheck payments can be set for instant download or delayed until cleared
- Uses MD5 and Paypal's IPN system for maximum security.
- Built in or user defined template for email sent to purchaser.
- Built in or user defined download page.
- Supports download resume and download managers.
- Email and download page templates can be product specific.
- Supports physical products.
- Can generate software unlock keys or serial numbers from a list, using a user provided algorithm, Clicklocker or by using Software Passport (Armadillo).
- Can protect access to a html or PHP page instead of a download.
- Product specific template segment system.
- Sell your Software Passport (Armadillo) protected software with Paypal as well as Digital River.
- Allows secure links to be emailed manually as well if necessary.
- Optional