Reply To: Paypal payment not registering as paid in dashboard

You get that mail if the payment isn’t successfull for any reason.
This can happen with payments in other currencys, if the owner isn’t the same or the status isn’t Complete.
And it happen’s of course if paypal say’s it’s a false/not existing payment. Maybe you used the Sandbox without using SSL, then it will always return false.

If everything of this is correct try to view your “IPN History” in the PayPal settings. There are sometimes more extended error reasons.