PAYPAL IPN & PDT fail

Question

I am working on a ordering system, where the payment is taken using PayPal.

Currently have issues with IPN.

I have used the sample IPN code provided via this link below:

https://github.com/paypal/ipn-code-samples/blob/master/paypal_ipn.php

However every time I test IPN via IPN Simulator it shows below error:

IPN was not sent, and the handshake was not verified. Please review your information.

Answer 1

许多人建议IPN模拟器已损坏。