How To Fix CNV_DMC_MC_EXCEPTION234 - Message ID already exists

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 234

• Message text: Message ID already exists

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_MC_EXCEPTION234 - Message ID already exists ?

  The SAP error message CNV_DMC_MC_EXCEPTION234 with the description "Message ID already exists" typically occurs during data migration or conversion processes, particularly when using the SAP Data Migration Cockpit (DMC) or similar tools. This error indicates that there is a conflict with an existing message ID in the system, which can happen for various reasons.
  Causes:
  
  Duplicate Message IDs: The most common cause is that the message ID you are trying to create or use already exists in the system. This can happen if the same migration object or message is being processed multiple times.
  Configuration Issues: There may be issues in the configuration of the migration project or the mapping of data that leads to the generation of duplicate message IDs.
  Data Consistency: If the data being migrated has inconsistencies or duplicates, it may lead to conflicts in message IDs.
  
  Solutions:
  
  Check for Duplicates: Review the migration logs and the data being processed to identify if there are any duplicate entries or message IDs. Ensure that each message ID is unique.
  Adjust Migration Settings: If you are using a migration template or predefined settings, check to ensure that they are correctly configured to avoid generating duplicate message IDs.
  Clear Temporary Data: If the error persists, consider clearing any temporary data or logs related to the migration process. This may involve resetting the migration project or cleaning up the staging area.
  Review Mapping and Transformation Rules: Ensure that the mapping and transformation rules defined in the migration cockpit do not lead to the creation of duplicate message IDs.
  Consult Documentation: Refer to the SAP documentation for the Data Migration Cockpit for any specific guidelines or troubleshooting steps related to this error.
  Contact SAP Support: If the issue cannot be resolved through the above steps, consider reaching out to SAP support for assistance. They may provide insights specific to your system configuration and migration scenario.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional troubleshooting steps.
  Migration Cockpit Documentation: Review the official SAP documentation for the Data Migration Cockpit, which may provide insights into best practices and common issues.
  Community Forums: Engage with the SAP Community or forums where other users may have encountered similar issues and can share their solutions.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.