Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 449
Message text: Error while writing table RFDT for reference number &1
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The SAP error message CNV_20100449, which indicates an error while writing to the table RFDT for a reference number, typically arises during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error can occur due to various reasons, including data inconsistencies, missing entries, or issues with the migration logic. Causes: Data Inconsistencies: The data being migrated may have inconsistencies or invalid entries that prevent successful writing to the RFDT table. Missing Reference Data: The reference number specified may not exist in the source data or may not be properly mapped. Technical Issues: There could be technical issues such as database locks, insufficient authorizations, or system performance problems.
Configuration Issues: Incorrect configuration settings in the migration tool or the source system can lead to this error. Solutions: Check Data Consistency: Review the data being migrated for any inconsistencies or invalid entries. Ensure that all required fields are populated correctly. Verify Reference
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