Message type: E = Error
Message class:  CNV_20375_CHECK - Message Class for 20375 Checks 
Message number: 012
Message text: All provided source cost elements exist
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The SAP error message CNV_20375_CHECK012 typically occurs during a data migration or conversion process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that all provided source cost elements exist, which means that the system is expecting certain cost elements to be present in the source data but is unable to find them.
Cause: Missing Cost Elements: The error usually arises when the cost elements specified in the migration data do not exist in the source system or are not correctly mapped. Incorrect Mapping: There may be an issue with how the cost elements are mapped from the legacy system to the target system. Data Inconsistencies: There could be inconsistencies in the data being migrated, such as typos or incorrect identifiers for cost elements.
Solution: Verify Cost Elements: Check the source system to ensure that all the cost elements you are trying to migrate actually exist. You can do this by
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