The AR Invoice + Payment function is typically used when creating sales invoices for walk-in customers. For these one-time customers, no individual Business Partner Master Data records are maintained; presumably, no credit line is extended. Thus, when posting their invoices, full payments are required in the AR Invoice + Payment function. The generic BP code, used for one-time customers, in such transactions is set up in the Administration -> Setup -> Financials -> G/L Account Determination -> Sales Tab: General.
The default Customer for AR Invoice + Payment can also be set up per user in the Administration -> Setup -> General -> Users: Defaults field.
Incoming payment transactions are created simultaneously with the sales invoice transactions (AR Invoice + Payment or AR Invoice) and can be accessed through the Banking -> Incoming Payment window.
When posting a sales invoice using the AR Invoice function, the Incoming Payment window may open. Unless the payment details are entered, the sales invoice cannot be successfully added.
In this case, the system message 'Invoice and receipt must be paid exactly [Message 131-45]' is displayed.
If the Incoming Payment function opens when adding a regular AR Invoice, verify the default Payment Term assigned to the customer. In the payment term, ensure that the Open Incoming Payment field is set to No. If it is set to Cash, Cheques, Credit or Bank Transfer, the system will always open the Incoming Payment window after clicking Add in the AR Invoice function.