Following are the steps for Turn On
By default Auto Return is turned off.
1. Log in to your PayPal account at https://www.paypal.com then display the “My Account” Overview page.
2.Click on the Profile tab then “Profile Summary” page appears.
3. Under the Selling Preferences column, click the Website Payment Preferences link.
4. Auto Return for Website Payments, click the On radio button to enable Auto Return.
5. Click the Save button.