SAP Message WRF_REF012 - &4 Existing assignment cannot be overwritten

Diagnosis
The system cannot overwrite the reference assignment for the combinationof material &V1& and plant &V2&according to the general settings formultiple references.

System Response
The system cannot process this combination during the automaticassignment of references.

Procedure
If you want to change the existing reference assignment, use the dialogprogram References for Materials without History.