To use PDT, you must activate PDT and Auto Return in your PayPal account profile. You must also acquire a PDT identity token, 
which is used in all PDT communication you send to PayPal.

Follow these steps to configure your account for PDT:

1. Log in to your PayPal account.
2. Click the Profile subtab.
3. Click the My Selling Tools button in the left column.
4. Find the Selling online section and click Update in the Website preferences row.
5. Under Auto Return for Website Payments, click the On radio button.
6. For the Return URL, enter the URL on your site that will receive the transaction ID posted by PayPal after a customer payment.
Under Payment Data Transfer, click the On radio button.
7. Click Save.
8. Find the Selling online section and click Update in the Website preferences row again.
9. Scroll down to the Payment Data Transfer section of the page and take note of your PDT identity token.


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