Message type: E = Error
Message class:  CNV_PE_GEN - Messages for object generation 
Message number: 042
Message text: Structure information for extension parameter &1 not found
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The SAP error message CNV_PE_GEN042, which states "Structure information for extension parameter &1 not found," typically occurs in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools.
Cause: Missing Structure Definition: The error indicates that the system is unable to find the structure definition for the specified extension parameter. This could be due to: The structure not being defined in the system. The structure being incorrectly configured or not activated. The extension parameter being incorrectly referenced in the migration or conversion process. Incorrect Configuration: If the migration project or the data model has been incorrectly set up, it may lead to this error. Transport Issues: If the relevant transport requests containing the structure definitions have not been imported into the system, this could also lead to the error.
Solution: Check Structure Definition: Verify that the structure for the extension parameter exists in the system. You can do this
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