Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 304
Message text: No splits of securities account groups
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The SAP error message CNV_20200_CHECK304 with the description "No splits of securities account groups" 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 there are issues related to the configuration of securities account groups in the system.
Cause: Missing Configuration: The securities account groups may not be properly configured in the system. This can happen if the necessary account groups have not been defined or if there are inconsistencies in the configuration. Data Inconsistencies: The data being migrated may not align with the expected structure or requirements of the target system, leading to issues with account group splits. Mapping Issues: There may be problems with the mapping of securities accounts during the migration process, causing the system to not recognize the splits.
Solution: Check Configuration: Verify that all necessary securities account groups are defined in the system. You can do this by
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