How To Fix CNV_DMC_MC_EXCEPTION021 - A field rule with this name already exists at project level

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_MC_EXCEPTION - Exception texts of Migration Object Modeller

• Message number: 021

• Message text: A field rule with this name already exists at project level

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION021 - A field rule with this name already exists at project level ?

  The SAP error message CNV_DMC_MC_EXCEPTION021 indicates that there is a conflict due to a field rule with the same name already existing at the project level in the Data Migration Cockpit (DMC) or during a data migration process. This typically occurs when you are trying to create or modify a field rule that has already been defined in the project.
  Cause:
  
  Duplicate Field Rule: The most common cause is that a field rule with the same name has already been created in the project. This can happen if multiple users are working on the same project or if there was an attempt to create a field rule with a name that is not unique.
  Project Configuration: The project may have been configured in such a way that it does not allow duplicate field rules, leading to this error when a duplicate is detected.
  
  Solution:
  
  
  Check Existing Field Rules: 
  
  Navigate to the project in the Data Migration Cockpit.
  Look for the existing field rules and check if the one you are trying to create already exists.
  If it does, you can either modify the existing rule or delete it if it is no longer needed.
  
  
  
  Rename the New Field Rule: 
  
  If you need to create a new field rule, consider renaming it to ensure it is unique within the project.
  
  
  
  Review Project Documentation: 
  
  Ensure that there is proper documentation of the field rules being created to avoid conflicts in the future.
  
  
  
  Collaboration: 
  
  If multiple team members are working on the same project, establish a communication protocol to avoid creating duplicate field rules.
  
  
  
  Consult SAP Notes: 
  
  Check for any relevant SAP Notes or documentation that may provide additional insights or updates regarding this error.
  
  
  
  Related Information:
  
  Data Migration Cockpit (DMC): This is a tool used in SAP for data migration processes, allowing users to map, transform, and load data into SAP systems.
  Field Rules: These are rules defined to control how data is transformed and loaded during the migration process. They can include validations, transformations, and mappings.
  SAP Community and Support: If the issue persists, consider reaching out to the SAP Community or SAP Support for further assistance.
  
  By following these steps, you should be able to resolve the error CNV_DMC_MC_EXCEPTION021 and continue with your data migration process.