Message type: E = Error
Message class:  CNV_20400_CHECK - Messages for check functions (controlling area merge) 
Message number: 064
Message text: Controlling area &1 (has priority)
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The SAP error message CNV_20400_CHECK064 typically relates to issues encountered during data migration or conversion processes, particularly in the context of controlling areas in SAP systems. This error indicates that there is a priority conflict or inconsistency with the controlling area specified.
Cause: The error message CNV_20400_CHECK064 can occur due to several reasons, including: Inconsistent Data: The controlling area specified may not be consistent with the data being migrated or converted. Priority Conflicts: There may be multiple controlling areas with overlapping or conflicting priorities, leading to ambiguity in the data processing.
Configuration Issues: The controlling area may not be properly configured in the system, or there may be missing or incorrect settings related to the controlling area. Data Mapping Errors: Errors in the mapping of data from the source system to the target system can also trigger this error.
Solution: To resolve the CNV_20400_CHECK064 error, you can take the following steps: Check Configuration: Verify the configuration of the controlling
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