How To Fix CNV_DMC_MC_EXCEPTION218 - Source structure is mapped to a target structure; cannot be read-only

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 218

• Message text: Source structure is mapped to a target structure; cannot be read-only

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION218 - Source structure is mapped to a target structure; cannot be read-only ?

  The SAP error message CNV_DMC_MC_EXCEPTION218 typically occurs during data migration processes, particularly when using the SAP Data Migration Cockpit (DMC) or similar tools. This error indicates that there is an issue with the mapping of source and target structures in the data migration process. Specifically, it suggests that the source structure is mapped to a target structure that is set to read-only, which prevents the system from writing data to it.
  Cause:
  
  Read-Only Target Structure: The target structure in the migration process is configured as read-only, which means that it cannot accept any data from the source structure.
  Incorrect Mapping: There may be an incorrect mapping configuration between the source and target structures, leading to this error.
  Authorization Issues: The user executing the migration may not have the necessary permissions to write to the target structure.
  Technical Constraints: Certain technical constraints or settings in the system may prevent writing to the target structure.
  
  Solution:
  
  
  Check Target Structure Configuration:
  
  Verify the configuration of the target structure in the migration cockpit. Ensure that it is not set to read-only.
  If it is intended to be writable, adjust the settings accordingly.
  
  
  
  Review Mapping:
  
  Review the mapping between the source and target structures. Ensure that the mapping is correct and that the target structure is designed to accept data from the source.
  
  
  
  User Permissions:
  
  Check the user permissions for the account executing the migration. Ensure that the user has the necessary authorizations to write to the target structure.
  
  
  
  Consult Documentation:
  
  Refer to the SAP documentation for the Data Migration Cockpit or the specific migration tool you are using. There may be specific guidelines or settings that need to be adjusted.
  
  
  
  Test Migration:
  
  If possible, perform a test migration with a small dataset to see if the issue persists. This can help isolate the problem.
  
  
  
  Contact SAP Support:
  
  If the issue cannot be resolved through the above steps, consider reaching out to SAP Support for further assistance. Provide them with detailed information about the error and the context in which it occurs.
  
  
  
  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 for best practices and configuration guidelines.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.