SAP Note 16922 - Invoice verification: reversal, ext. no. assignment

Symptom:

Key word: MR08
Reversing invoices: if the reversal document type for the invoice document type has external number assignment, the action is prevented from Release 2.2 onwards with error message F5092 "Document type ... must have internal number assignment for reversal" or M8365 "Document cannot be reversed". Up to Release 2.1, a screen was displayed in this situation that enabled entry of an external document number for the reversal document.

Cause and prerequisites

Not an error. It should no longer be possible to perform reversals using document types with external number assignment. This activity was erroneously allowed until Release 2.1, and was corrected in Release 2.2.

Solution
You must make sure that a reversal document type is specified with internal number assignment for every relevant document type.
In Customizing for invoice verification, the reversal document type is found under Activities -> Incoming invoice -> Document number/number range, sub-item Document type. The detail screen for the document type contains the field "Reversal document type" in the "Properties" group.
To enable reversal using document types with external number assignment in invoice verification, you can make the following modifications.
Change program LMRBIU01; insert the lines marked with "INSERT below:
...
SELECT SINGLE * FROM TCURM.

IF SY-TCODE = 'MR08'. "INSERT
MODUS = 'E'. "INSERT
ENDIF. "INSERT

CLEAR: BDCTAB,
...