Diagnosis
You entered an invoice with negative delivery costs. When simulatingor posting the invoice, the system divides these delivery costs amongthe individual items. Since the delivery costs are negative, theitem amounts are reduced. In item &V1& this leads to a value that is 0or even negative. This is not allowed.

Procedure
Check the delivery costs and the amount in itemV1. if both are correct, you must manually divide the deliverycosts among the individual items with no amount being negative or0.