How To Fix CNV_DMC_MC_EXCEPTION018 - An internal rule with this name already exists

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 018

• Message text: An internal rule with this name already exists

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION018 - An internal rule with this name already exists ?

  The SAP error message CNV_DMC_MC_EXCEPTION018 typically occurs during data migration processes, particularly when using the SAP Data Migration Cockpit (DMC). This error indicates that there is an attempt to create or define a migration rule that already exists in the system, leading to a conflict.
  Cause:
  The primary cause of this error is that the migration rule you are trying to create has the same name as an existing rule in the system. This can happen if:
  
  You are importing or creating migration rules that have not been uniquely named.
  There is a duplication in the naming convention used for the migration rules.
  The migration project is being executed multiple times without proper cleanup of previous configurations.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check Existing Rules: 
  
  Navigate to the migration cockpit and check the list of existing migration rules. Look for the rule name that is causing the conflict.
  
  
  
  Rename the Rule: 
  
  If you find that the rule name already exists, consider renaming the new rule to something unique that does not conflict with existing names.
  
  
  
  Delete or Modify Existing Rule: 
  
  If the existing rule is no longer needed, you can delete it. Alternatively, you can modify the existing rule if it is appropriate to do so.
  
  
  
  Review Migration Project: 
  
  Ensure that your migration project is set up correctly and that there are no unintended duplications in the rules being created.
  
  
  
  Consult Documentation: 
  
  Refer to the SAP documentation for the Data Migration Cockpit for best practices on naming conventions and managing migration rules.
  
  
  
  Check for Updates: 
  
  Ensure that your SAP system is up to date with the latest patches and updates, as there may be fixes related to this issue in newer versions.
  
  
  
  Related Information:
  
  SAP Notes: Check SAP Notes related to the Data Migration Cockpit for any known issues or additional guidance on handling migration rules.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have found.
  Documentation: Review the official SAP documentation for the Data Migration Cockpit for detailed instructions on managing migration rules and troubleshooting common errors.
  
  By following these steps, you should be able to resolve the CNV_DMC_MC_EXCEPTION018 error and proceed with your data migration tasks.