Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 420
Message text: &1 records were added; &2 records were changed
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The SAP error message CNV_20100420 typically relates to data migration or data conversion processes, particularly when using SAP's tools for data transfer or transformation. This message indicates that a certain number of records were added and a certain number were changed during the migration process.
Cause: Data Migration Issues: This message often arises during data migration activities, where records from a legacy system are being imported into an SAP system. The message indicates that some records were successfully added to the target system, while others were modified. Data Quality Issues: If the source data has inconsistencies or does not meet the validation rules of the target system, it may lead to records being changed or rejected. Mapping Errors: Incorrect mapping of fields between the source and target systems can lead to unexpected changes in records. Duplicate Records: If the migration process encounters duplicate records, it may add new records while updating existing ones.
Solution: Review Migration Logs:
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