Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 156
Message text: &1 &2: No TDetObject was assigned
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The SAP error message CNV_10020156 with the text "No TDetObject was assigned" 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 the system is unable to find a corresponding TDetObject (Transfer Data Object) for the data being processed.
Cause: Missing Configuration: The TDetObject may not be properly configured or assigned in the migration project. Data Mapping Issues: There may be issues with the mapping of source data to the target structure, leading to the absence of a defined TDetObject. Inconsistent Data: The source data might not conform to the expected format or structure, causing the system to fail in identifying the appropriate TDetObject. Technical Issues: There could be underlying technical issues, such as missing transport requests or incomplete setups in the migration cockpit.
Solution: Check Configuration: Verify that the TDetObject is correctly configured in the migration project. Ensure that all necessary
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