Diagnosis
You have called up a bill of material in a dependency for an objectwhose type is only known as class (that is, the type has not yet beenclearly specialized for a specific material). Based on the data, thesystem cannot determine a clear bill of material for the object.

System Response
Error message while downloading.

Procedure
Check the affected dependency.
Formulate references to materials in Constraints and Rules withIS_OBJECT instead of IS_A.