“WP Secure Links” is a WordPress Plugin that helps you offer downloads safely and securely. The Download Links created by “WP Secure Links” cannot be copied or distributed. You can create a download area on a WordPress Page. A short tag in the WordPress editor helps you add secure links to downloadable files on WordPress Pages and Posts.

http://codecanyon.net/item/wp-secure-links/4418678
     
 

http://ul.to/e6sn73q2