How To Fix CM_MDG_BS_MAT_GEN021 - Change of Base UoM is only possible, if all additional UoMs are adjusted

SAP Error Message - Details

• Message type: E = Error

• Message class: CM_MDG_BS_MAT_GEN - Material Messages

• Message number: 021

• Message text: Change of Base UoM is only possible, if all additional UoMs are adjusted

What causes this issue?

Material &SYST-MSGV1&: Base unit of measure &SYST-MSGV2& cannot be
changed

System Response

The base unit of measure for material &SYST-MSGV1& was changed. There
are already alternative units of measure defined that refer to the base
unit of measure. The base unit of measure must not be changed while
these alternative units of measure exist. The base unit of measure is
reset to its current value.

How to fix this error?

Before the base unit of measure can be changed, the alternative units of
measure have to be deleted.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CM_MDG_BS_MAT_GEN021 - Change of Base UoM is only possible, if all additional UoMs are adjusted ?

  The SAP error message CM_MDG_BS_MAT_GEN021 indicates that a change to the Base Unit of Measure (UoM) for a material is not allowed unless all additional Units of Measure associated with that material are also adjusted accordingly. This is a common restriction in SAP Master Data Governance (MDG) for materials to ensure data consistency and integrity.
  Cause:
  
  Inconsistent UoM Configuration: The system requires that if the Base UoM is changed, all additional UoMs must be recalibrated to maintain the relationship between the Base UoM and the additional UoMs.
  Data Integrity Rules: SAP enforces strict data integrity rules to prevent discrepancies in inventory management, pricing, and reporting.
  
  Solution:
  To resolve this error, you need to ensure that all additional UoMs are adjusted when changing the Base UoM. Here are the steps to follow:
  
  Identify Additional UoMs: Check the material master data to identify all additional UoMs that are currently defined for the material.
  Adjust Additional UoMs: For each additional UoM, calculate the appropriate conversion factors based on the new Base UoM and update them accordingly.
  Change Base UoM: Once all additional UoMs have been adjusted, you can proceed to change the Base UoM.
  Validation: After making the changes, validate the material master data to ensure that all UoMs are consistent and correctly defined.
  
  Related Information:
  
  Material Master Data: Understanding how UoMs are defined in the material master is crucial. The Base UoM is the primary unit used for inventory management, while additional UoMs are used for sales, purchasing, and other processes.
  Conversion Factors: Familiarize yourself with how conversion factors are calculated and maintained in SAP. This is essential for ensuring that the relationships between different UoMs are preserved.
  SAP Documentation: Refer to SAP Help documentation for detailed guidelines on managing material master data and UoM settings.
  Testing: After making changes, it is advisable to test the material in a non-production environment to ensure that the changes do not affect other processes.
  
  By following these steps, you should be able to resolve the error and successfully change the Base UoM for the material in SAP.