Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 421
Message text: Maintain all relevant entries
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The SAP error message CNV_20100421: Maintain all relevant entries typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that there are missing or incomplete entries in the configuration or mapping tables that are necessary for the migration process to proceed.
Cause: Incomplete Configuration: The migration settings or mapping configurations may not be fully defined. This can happen if certain required fields or parameters are left blank or not properly set up. Missing Master Data: The error may arise if there are missing master data entries that are required for the migration process. Inconsistent Data: If the data being migrated does not meet the expected format or constraints, it can lead to this error. Dependencies Not Resolved: There may be dependencies between different data objects that have not been resolved, leading to incomplete entries.
Solution: Review Configuration: Go through the migration configuration settings
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