Further to my question and awesome answers from the previous thread,
Redirection / Return Check in PHP
I would also love to know, if a payment confirmation page is returned to my website from PayPal, how can I 100% sure that it is coming from paypal and the payment is made?
Regards,
Andy
To make sure the request is coming from PayPal you can try resolving the IP address:
You can (and should) also request
https://www[.sandbox].paypal.com/cgi-bin/webscr/with the same data your received in POST and append thecmd=>_notify-validatekey-value pair to the request, if the response isVERIFIEDthe data is valid.See also this question: PayPal IPN Security