Message type: E = Error
Message class:  CNV_20306_CHECK - Message Class for package CNV_20306_CHECK 
Message number: 028
Message text: No implicit controlling area merge found
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The SAP error message CNV_20306_CHECK028 with the description "No implicit controlling area merge found" typically occurs during the data migration process, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that the system could not find a valid implicit merge of controlling areas, which is necessary for the migration of controlling area-related data.
Cause: Controlling Area Configuration: The error often arises when there are multiple controlling areas in the source system that do not have a defined relationship or merge path. This can happen if the controlling areas are not set up correctly or if there are inconsistencies in the configuration. Data Migration Settings: The migration settings may not be correctly configured to handle the merging of controlling areas, leading to the system being unable to find a suitable merge path. Inconsistent Data: There may be inconsistencies in the data related to controlling areas, such as missing
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