Message type: E = Error
Message class:  CNVOM_DEL_TASK - Object-based Deletion: messages 
Message number: 021
Message text: No data deleted due to simulation
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The SAP error message CNVOM_DEL_TASK021 indicates that no data was deleted during a simulation run of a data deletion task. This message is part of the SAP data migration and conversion tools, particularly in the context of the SAP S/4HANA migration process or data cleansing activities.
Cause: Simulation Mode: The error occurs because the task is being executed in simulation mode. In this mode, the system checks what would happen if the deletion were to occur, but it does not actually delete any data. No Data Matching Criteria: There may be no data that meets the criteria specified for deletion. This could be due to incorrect selection criteria or filters that do not match any existing records. Data Already Deleted: The data intended for deletion may have already been removed in a previous run or is not present in the system.
Configuration Issues: There may be issues with the configuration of the deletion task or
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