Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 012
Message text: No header tables maintained
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The SAP error message CNV_NCE_BAS012: No header tables maintained typically occurs in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that the system is unable to find the necessary header tables that are required for the migration process.
Cause: Missing Configuration: The header tables that are required for the specific migration scenario have not been maintained or configured in the system. Incorrect Migration Object: The migration object you are trying to use may not be set up correctly, or it may not correspond to the data you are trying to migrate. Transport Issues: If the migration objects were transported from another system, there may have been issues during the transport that led to missing or incomplete configurations. Authorization Issues: Lack of proper authorizations to access the necessary tables or configurations can also lead to this error.
Solution: Check Configuration: Ensure that
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