Message type: E = Error
Message class:  CNV_MBT_46 - PCL message class 
Message number: 186
Message text: Fieldname not maintained
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The SAP error message CNV_MBT_46186: Fieldname not maintained 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 a required field name is not properly maintained or mapped in the migration settings.
Cause: Missing Field Mapping: The field that is expected to be populated during the migration process is not mapped correctly in the migration template or configuration. Incorrect Configuration: The migration settings may not have been configured to include the necessary fields, or the fields may have been omitted inadvertently. Data Structure Changes: If there have been changes in the data structure (e.g., during an upgrade or system conversion), the expected fields may no longer exist or may have been renamed.
Solution: Check Migration Template: Review the migration template or configuration settings to ensure that all required fields are included and correctly mapped. Field Mapping: Ensure that the field in question
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