How To Fix CNV_DMC_SIN339 - Update or enhance of already existing record &1 is not allowed

CNV_DMC_SIN339 - Overview

• Message type: E = Error

• Message class: CNV_DMC_SIN - Messages for s-innovations migration

• Message number: 339

• Message text: Update or enhance of already existing record &1 is not allowed

What causes this issue?

You transferred a value in one of the fields provided on sheet 'General
Data', but the supplier master &V1& already exists.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

It is not allowed to change or enhance an already existing record in the
related supplier master: Therefor you can use the Mass Maintenance App.
For further information, refer to online documentation of the Mass
Maintenance App.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

CNV_DMC_SIN339 - Details

• The SAP error message CNV_DMC_SIN339 typically occurs during data migration processes, particularly when using the SAP Data Migration Cockpit (DMC) or similar tools. This error indicates that there is an attempt to update or enhance an already existing record in a way that is not permitted by the system.
  
  Cause:
  
  Duplicate Records: The error often arises when there is an attempt to insert or update a record that already exists in the target system. This can happen if the data being migrated contains duplicates or if the migration logic is incorrectly configured.
  Key Violations: The record being processed may have a unique key constraint that is violated by the incoming data.
  Data Integrity Rules: The system may have specific rules or validations that prevent certain updates to existing records, especially if they are linked to other data or processes.
  Incorrect Mapping: The mapping of fields between the source and target systems may not be correctly