Message type: E = Error
Message class:  CNV10400 - Messages for package 10400 (characteristics) 
Message number: 038
Message text: Characteristics which cannot be converted
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The SAP error message CNV10400038, which states "Characteristics which cannot be converted," typically occurs during data migration or conversion processes, particularly when using SAP's tools for data migration, such as the SAP S/4HANA Migration Cockpit or other data transfer tools.
Cause: This error usually arises due to one or more of the following reasons: Incompatible Data Types: The characteristics in the source system may not match the expected data types in the target system. For example, a characteristic defined as a string in the source may be expected as a numeric type in the target. Missing Characteristics: The characteristics that are being referenced in the migration process may not exist in the target system or may have been incorrectly defined. Data Mapping Issues: There may be issues with the mapping of characteristics from the source to the target system, leading to discrepancies. Custom Characteristics: If there are custom characteristics in the source system that do not
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