When processing Customer Payments the message "Specified invoice does not exist or does not apply to this customer" normally means that the payment is for an invoice that has not yet been entered or imported. This will occur if processing of Customer Payments gets ahead of importing Sales.
This can also occur when the invoice identified is for a different customer to the payment. This can arise when there are duplicate invoice numbers as the wrong invoice may have been picked up and is for a different customer.
1 post • Page 1 of 1