Please check your server that handles PayPal Instant Payment Notifications (IPN). IPNs sent to the following URL(s) are failing:
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.
I also have errors in Xenforo.
This is odd because all I have done is upgrade Xenforo from 1.2.x through the upgrades. It stopped working a month ago. Paypal is good. IPN is setup with above link in place.