Message type: E = Error
Message class:  CNV_10520 - Conversion module of FI-CA FIKEY-logic 
Message number: 034
Message text: Starting merge simulation with &1 reconciliation keys
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The SAP error message CNV_10520034, which states "Starting merge simulation with &1 reconciliation keys," typically occurs during the data migration process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This message indicates that there is an issue related to the reconciliation keys during the merge simulation phase of the data migration.
Cause: Reconciliation Key Issues: The error often arises when there are inconsistencies or issues with the reconciliation keys in the source data. This could be due to duplicate keys, missing keys, or keys that do not match the expected format. Data Quality Problems: Poor data quality in the source system can lead to issues during the merge simulation, such as invalid or incomplete records.
Configuration Issues: Incorrect configuration settings in the migration cockpit or the data mapping can also lead to this error.
Solution: Check Reconciliation Keys: Review the reconciliation keys in the source data. Ensure that they are unique and correctly
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