How To Fix CNV_DMC_SIN336 - Changing of already existing values is not allowed

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 336

• Message text: Changing of already existing values is not allowed

What causes this issue?

You transferred the value &V1& in one of the fields provided on sheet
'Basic Data' which has already an existing value &V2& in the related
material master &V3&.

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 already existing values in the related
material 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.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_SIN336 - Changing of already existing values is not allowed ?

  The SAP error message CNV_DMC_SIN336 ("Changing of already existing values is not allowed") typically occurs during data migration or data conversion processes, particularly when using the SAP Data Migration Cockpit (DMC) or similar tools. This error indicates that the system is trying to change values in a target table that are already populated, which is not permitted under the current configuration or rules of the migration process.
  Cause:
  
  Existing Data Conflict: The target table already contains data that conflicts with the incoming data from the source. The migration process is attempting to insert or update records that already exist in the target system.
  Configuration Settings: The migration settings may be configured to prevent updates to existing records, allowing only new records to be created.
  Data Mapping Issues: There may be issues with how the source data is mapped to the target structure, leading to attempts to overwrite existing values.
  
  Solution:
  
  Review Existing Data: Check the target table to see what data already exists. You may need to decide whether to keep the existing data or to remove it before running the migration again.
  Adjust Migration Settings: If the intention is to update existing records, you may need to adjust the migration settings to allow updates. This could involve changing the configuration in the DMC or the specific migration tool you are using.
  Data Preparation: Ensure that the source data is prepared correctly. If you are trying to insert new records, make sure that the keys or identifiers do not conflict with existing records in the target system.
  Use a Different Migration Approach: If the current approach does not allow for the necessary changes, consider using a different method for data migration that supports updates to existing records.
  Consult Documentation: Refer to the SAP documentation for the specific migration tool you are using to understand the rules and configurations that govern data updates.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may provide additional insights or solutions for this specific error message.
  Data Migration Cockpit (DMC): Familiarize yourself with the functionalities and limitations of the DMC, as it may have specific settings that affect how data is migrated.
  Testing: Before performing a full migration, conduct tests with a smaller dataset to identify potential issues without affecting the entire system.
  Backup: Always ensure that you have backups of your data before performing migration tasks, especially if you are making changes to existing records.
  
  If the issue persists after trying the above solutions, consider reaching out to SAP support or consulting with an SAP expert who can provide more tailored assistance based on your specific scenario.