Each day I've been receiving the following email from Paypal:
"Please check your server that handles PayPal Instant Payment Notifications (IPN). IPNs sent to the following URL(s) are failing:"
https://www.spminiatures.com/store/ipn_main_handler.php

I am receiving IPN's from orders so I don't understand why I'm receiving this message and it started a couple of weeks ago. When I check the Paypal IPN history it shows it as retrying many, many times. Paypal tells me it's my server problem. I checked the file URL and it's fine.

Any ideas?

Thanks
Carol