Message type: E = Error
Message class:  CNV_20340 - Messages for cycle conversion 
Message number: 010
Message text: Cycle mapping (controlling area) not set to "visible"
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The SAP error message CNV_20340010 indicates that there is an issue with cycle mapping in the context of controlling areas during a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error message "Cycle mapping (controlling area) not set to 'visible'" suggests that the cycle mapping for the controlling area is not properly configured or is not set to be visible in the system. This can occur due to several reasons, including:
Configuration Issues: The cycle mapping may not have been defined correctly in the system. Visibility Settings: The visibility settings for the cycle mapping may not be enabled, preventing the system from recognizing it during the migration process. Data Inconsistencies: There may be inconsistencies or missing data related to the controlling area or cycle mapping in the source or target system.
Solution: To resolve this
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