How To Fix CNV_DMC_MC_EXCEPTION138 - Cannot generate migration objects; see long text

SAP Error Message - Details

• Message type: E = Error

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

• Message number: 138

• Message text: Cannot generate migration objects; see long text

What causes this issue?

When you choose Generate Migration Object, the system must first check
whether the structures in a migration object are in sync with the same
structures in the ABAP Dictionary. If the structures are not in sync,
the migration objects cannot be generated. To synchronize the structures
in a migration object with the structures in the ABAP Dictionary, in the
menu choose Migration Object and then Synchronize Structures.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_MC_EXCEPTION138 - Cannot generate migration objects; see long text ?

  The SAP error message CNV_DMC_MC_EXCEPTION138 typically occurs during the data migration process when using the SAP Data Migration Cockpit (DMC). This error indicates that the system cannot generate migration objects, which are essential for the data migration process.
  Causes:
  
  Configuration Issues: There may be misconfigurations in the migration settings or parameters.
  Missing Objects: Required migration objects or structures may be missing in the source or target system.
  Authorization Problems: The user executing the migration may not have the necessary authorizations to create or access migration objects.
  Data Model Issues: There could be inconsistencies or issues in the data model that prevent the generation of migration objects.
  Technical Errors: There may be underlying technical issues, such as database connectivity problems or system performance issues.
  
  Solutions:
  
  Check Configuration: Review the migration configuration settings to ensure they are correctly set up.
  Verify Migration Objects: Ensure that all required migration objects are available and correctly defined in both the source and target systems.
  User Authorizations: Confirm that the user has the necessary authorizations to perform the migration tasks. This may involve checking roles and permissions in the SAP system.
  Review Data Model: Analyze the data model for any inconsistencies or errors that could be causing the issue. This may involve checking for missing fields or incorrect data types.
  Check Logs: Look at the detailed logs or long text associated with the error message for more specific information about what went wrong.
  System Performance: Ensure that the system is performing optimally and that there are no connectivity issues with the database or other components.
  
  Related Information:
  
  SAP Notes: Check SAP Notes related to the error message for any patches or updates that may address the issue.
  Documentation: Refer to the official SAP documentation for the Data Migration Cockpit for guidance on configuration and troubleshooting.
  Community Forums: Engage with the SAP Community or forums where other users may have encountered similar issues and can provide insights or solutions.
  
  If the problem persists after trying the above solutions, it may be beneficial to contact SAP support for further assistance.