How To Fix CNV_DMC_MC001 - Changes are only allowed for customer fields

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_MC - Migration Object Modeler

• Message number: 001

• Message text: Changes are only allowed for customer fields

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC001 - Changes are only allowed for customer fields ?

  The SAP error message CNV_DMC_MC001: Changes are only allowed for customer fields typically occurs during data migration or transformation processes, particularly when using the SAP Data Migration Cockpit (DMC) or similar tools. This error indicates that the system is trying to modify a field that is not designated as a customer field, meaning that it is a standard field that should not be altered during the migration process.
  Cause:
  
  Modification of Standard Fields: The error arises when there is an attempt to change standard SAP fields that are not intended to be modified. The system restricts changes to ensure data integrity and compliance with SAP's data model.
  Incorrect Mapping: The mapping configuration in the migration tool may incorrectly specify standard fields for updates instead of customer-defined fields.
  Data Source Issues: The data being imported may contain values or structures that are not compatible with the target system's expectations for standard fields.
  
  Solution:
  
  Review Field Mapping: Check the mapping configuration in the migration tool to ensure that only customer fields are being modified. Ensure that standard fields are not included in the mapping for updates.
  Use Customer Fields: If you need to store additional information, consider using customer fields (custom fields) instead of trying to modify standard fields. You can create custom fields in the relevant tables if necessary.
  Data Validation: Validate the data being imported to ensure it adheres to the expected formats and values for the target fields. This may involve cleaning or transforming the data before migration.
  Consult Documentation: Refer to the SAP documentation for the Data Migration Cockpit or the specific migration tool you are using to understand the limitations and requirements regarding field modifications.
  Error Logs: Check the error logs for more detailed information about which specific fields are causing the issue. This can help pinpoint the exact problem.
  
  Related Information:
  
  SAP Notes: Look for relevant SAP Notes that may address this specific error or provide guidance on best practices for data migration.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have found.
  Training and Documentation: Ensure that your team is trained on the data migration tools and understands the implications of modifying standard fields versus customer fields.
  
  By following these steps, you should be able to resolve the CNV_DMC_MC001 error and successfully complete your data migration process.