Hi, Would you know exactly why I would be getting the above error message in my ipn.php file? Payment is not completed and the customer is not taken to the thanks page. aMember also does not activate customer membership account. What php variables should I look at? Seems to me that just one variable (payment) is out of balance with another. If you are an aMember expert who knows his php then maybe you can point me in the right direction to debug this problem. Thanks. Doobie