vBulletin Manual

1	Log in to your PayPal account
2	Click on the Profile subtab
3	Click on the Instant Payment Notification Preferences link in the 'Selling Preferences' column
4	Click Edit

You should now be presented with a screen containing the following:

Setting callback URL

Note:

If the Instant Payment Notification link is not present you will need to apply for Premier Account or a Business Account from PayPal.

Check the checkbox to activate Instant Payment Notification and enter the following URL below the checkbox.

https://www.example.com/forums/subscriptions/paypal.php

Click [Save]

Go to vBulletin Options > vBulletin Options > Paid Subscriptions (link) and enter your PayPal email address in the PayPal email field.