Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 275
Message text: Secondary cost element &1 &2 in controlling area &3 is missing in mapping
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The SAP error message CNV_20100275 indicates that there is a missing secondary cost element in the mapping for a specific controlling area. This error typically arises during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs when the system is trying to map a secondary cost element that does not exist in the specified controlling area. This can happen due to several reasons: Missing Configuration: The secondary cost element has not been created in the controlling area. Incorrect Mapping: The mapping file or configuration may not include the necessary secondary cost elements. Data Migration Issues: During data migration, the secondary cost elements may not have been included or were incorrectly referenced.
Solution: To resolve this error, you can follow these steps: Check Cost Element Configuration: Go to the SAP GUI and navigate to the transaction code KA03 (Display Cost Element). Enter the cost element number and the controlling area
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