JVZShare is a free addon powered by WPDigiPro plugin so, you don’t require any license key to use it.
Once the addon plugin is activated an input box will appear to assign a Default Secret Key.
Go to Dashboard > Settings > Others > JVZShare.
Note: Assign a 16 characters long key only.
Go to Products > Add New. Here, at the bottom of the page you’ll find JVShare settings.
Default Secret Key that you have created earlier will be mentioned here. IPN URL shown here should be copied to it’s related product created on JVShare account.