Message type: E = Error
Message class:  /SCMB/MC_PB_DEF -  
Message number: 174
Message text: Mat. &1 is child of ref. mat. &2; child-parent combinations not allowed
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The SAP error message /SCMB/MC_PB_DEF174 indicates that there is an issue with the relationship between materials in the SAP system, specifically in the context of parent-child relationships in the material master data. This error typically arises when you are trying to create or modify a material that is defined as a child of a reference material, but the system does not allow such combinations.
Cause: Parent-Child Relationship: The error occurs when you attempt to create or modify a material that is designated as a child of another material (the reference material), but the system settings or configuration do not permit this type of relationship. Configuration Settings: The configuration in the SAP system may not allow certain combinations of parent and child materials, leading to this error. Data Integrity Issues: There may be inconsistencies or incorrect data entries in the material master records that violate the expected parent-child relationships.
Solution: Check Material Master Data: Review the material
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