We are having problems with registrations made with PayPal being not completed/marked paid.

We are also getting the following email notice from paypal:

Please check your server that handles PayPal Instant Payment Notifications (IPN). IPNs sent to the following URL(s) are failing:



https://.../index.php?option=com_matukio&view=ppayment&task=status&pg_plugin=paypal&uuid=6f573837d.....14995441ce 



If you do not recognize this URL, you may be using a service provider that is using IPN on your behalf. Please contact your service provider with the above information. If this problem continues, IPNs may be disabled for your account. 



Thank you for your prompt attention to this issue.



Thanks,



PayPal

Our settings in the Payment - Paypal plugin are:

* Enter Paypal email Address (confirmed that it is accurate)
* Enable sandbox mode: No
* secure post (use https)? Yes (we also use https throughout our web site)
* Always accept PayPal IPN (insecure): No
* Plugin Name: Online Payment (via PayPal)

I'm wondering about the "Always accept PayPal IPN). Is the "Insecure" related to the question or the NO answer (which is just next to the word insecure)?

Also, I did read something about hosting companies possibly blocking this; however, we also have Hikashop installed on this site and PayPal is working fine for that extension (not sure if that has any impact).

Are there any instructions on how to properly configure this to work (or can give an explanation how the hosting provider might be blocking PayPal with Matukio, but not with Hikashop?