SAP Message UCT8257 - Source selection derived from target field &1 is empty

Diagnosis
The system derives the source selection from the selection for targetfield &V1&. The resulting source selection is empty.

System Response
The system cannot read any source data.

Procedure
Examine the mapping rule for field &V1&. Make sure that the inversion ofthe mapping rule does not produce an empty selection or lead toconflicting values.