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Instant Payment Notification Manual

Using IPN

Getting set up to use IPN and validate notifications

Setting up IPN

To set up IPN:

1. Log in to your Business or Premier PayPal account.

2. Click the Profile subtab.

3. Click on the Instant Payment Notification Preferences link in the Selling

Preferences column.

4. Click Edit.

5. Click the checkbox and enter the URL at which you would like to receive your

IPN Notifications.

6. Click Save.

Notification Validation

To ensure that a payment has been made into your PayPal account, you must

verify that the email address used as your receiver_email has been registered and

confirmed in your PayPal account.

Once your server has received the Instant Payment Notification, you will need to

confirm it by constructing an HTTP POST to PayPal. Your POST should be sent to

https://www.paypal.com/cgi-bin/webscr. This post-back of the IPN data to a secure

PayPal URL (i.e., https://) prevents 'spoofing,' so you can be sure that the IPN came

from PayPal.

Note: It is possible to implement IPN without SSL (i.e., http://), but then the IPN

data that is received and posted back is not secure.

You must post all of the form variable you received exactly as you received them. You

will also need to append a variable named cmd with the value _notify-validate

(e.g., cmd=_notify-validate) to the POST string.

PayPal will respond to the post with a single word, “VERIFIED” or “INVALID,” in the

body of the response.