Message type: E = Error
Message class:  CNV_MBT_46 - PCL message class 
Message number: 394
Message text: Member ID &1 is already defined
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The SAP error message CNV_MBT_46394 indicates that there is a duplicate entry for a Member ID in the context of a data migration or conversion process. This error typically arises during the execution of a migration project, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error occurs when the system detects that the Member ID you are trying to define or import already exists in the target system or in the dataset being processed. This can happen due to: Duplicate Data: The source data being migrated contains duplicate entries for the same Member ID. Previous Migration Attempts: If a migration process was previously executed and not cleaned up properly, it may leave behind existing entries that conflict with new ones.
Configuration Issues: Incorrect configuration or mapping settings in the migration tool can lead to attempts to create duplicate entries.
Solution: To resolve the error, you can take the following steps: Check for Duplicates: Review
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