Given that E-Check is one of the methods that customers can pay using PayPal, it is advisable to Merchants that have chosen to configure PayPal as a payment method must set up the Instant Payment Notification (IPN) on PayPal's system. Merchants that have chosen Website Payments Standard must configure this setting also.
After After logging into your PayPal account, click the Profile (sub) tab. and in the Profile Summary screen, click the Instant Payment Notification Preferences link.
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Next, in the preferences page that appears, check the box that turns IPN "ON". Also enter +httpProfile button and select Profile and Settings.
Next click on My Selling Tools located on the left hand side of the screen as shown below.
Now click Update for the Instant Payment Notification section as shown below.
Click the "Choose IPN Settings" button as shown below.
Finally enter the URL https://secure.ultracart.com/cgi-bin/UCPayPalNotify+ into the URL box provided. Then click on the "Save" button. Anchor
Your newly configured IPN status will be shown in the IPN status screen. It is very important to insure that you have entered the correct URL. You can click the "Edit" button to make changes.