We use Opencart v1.5.5.1, and we love it. However, we receive weekly e-mails from PayPal:
We didn't really worry about this, as nothing happened so far. But 1 week ago, in the middle of the bank holiday weekend, PayPal has disabled our IPN. How can we make it sure it won't happen again? Is there any solution for this?...
Please check your server that handles PayPal Instant Payment Notifications (IPN). Instant Payment Notifications sent to the following URL(s) are failing:
http://www.example.com/ipn_main_handler.php
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.
Yours sincerely,
PayPal
...
Thank you very much in advance.
Kind Regards,
Tibor