We are running CB 2.0.15 and CBSubs 4.1.0 on Joomla 3.6.22.

I posted a month or two ago about an error I started getting when trying to process CBSubs payments through our PayPal sandbox account (with the new security structures). At the time I was on CB 1.9.1 and CBSubs 3.0.0 but have since upgraded both CB and CBSubs.

Working with PayPal and our hosting service, I have been able to demonstrate (using PayPal’s paypal_pdt.php and paypal_ipn.php test scripts) that the server communicates well with the PayPal sandbox and is able to process both PDT and IPN messages.

However, when I process a payment via CBSubs to the PayPal sandbox account, although the payment itself is received by PayPal, when the customer is returned to the website, the error message “Sorry no response for your payment from payment server (error 0). Please check your email and status later.” is shown. Paid Subscriptions/Notifications shows “IPN payment gateway communication error” and Paid Subscriptions/History shows “Paypal: Error at notification received: could not reach Paypal gateway for notification check at www.sandbox.paypal.com. COMMUNICATION ERROR”.

The live PayPal servers are not due to be moved to the new security structures until June next year and currently work well - we are only seeing the issue with the sandbox servers running the new security structures.

Please let me know if I can provide more information from the logs to help work out what is happening.

Thanks

Jim

Thanks Kyle. Just to be clear; in the Payment Gateway settings, are you referring to the PayPal Account and PDT Identity token (which are the same as we have always used), or to the optional PayPal API credentials? We have never used the latter and have always left those fields blank.

In our initial investigations (when we were still on 1.9.1. and 3.0.0), PayPal technical support ended up saying "I think there is an issue with the script being used. The server it is hosted on seems to be perfectly capable of communicating with the sandbox, so it comes down to analyzing the script itself." To set the record straight with them, is it correct to tell them that you have been able to successfully process CBsubs payments via PayPal's sandbox servers using their new security structures?

Thanks

Jim

By the way, I'm using the standard PayPal gateway.

For sure, the current sandbox environment is quite different from live - PayPal having introduced their new secure environment (due for implementation on the live environment in June next year) for testing purposes. I was previously able to process payments on the old sandbox setup, but not the new one

Anyway, I've checked and re-checked my API credentials as set out in your second paragraph and still get the communication error even though the payment itself is processed successfully in PayPal. PayPal have previously advised that the server can communicate OK, so I am really stuck at the moment.

Have the Joomlapolis team been able to process payments on the new sandbox environment OK? I'm wondering if I might have some of my settings wrong (e.g. the PCI-DSS "Keep HTTP/HTTPS mode as is" or "Force HTTPS on CBSubs forms"). I've tried both settings, though, and have also tried the Joomla "Force HTTPS" setting but no luck.