How To Fix DMCLG444 - Selection field &1 is not key field in header structure of conv.obj. &2

SAP Error Message - Details

• Message type: E = Error

• Message class: DMCLG - DMC Tool Development

• Message number: 444

• Message text: Selection field &1 is not key field in header structure of conv.obj. &2

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message DMCLG444 - Selection field &1 is not key field in header structure of conv.obj. &2 ?

  The SAP error message DMCLG444 indicates that there is an issue with a selection field that is not defined as a key field in the header structure of the conversion object. This error typically arises during data migration or data transfer processes, particularly when using tools like the Data Migration Cockpit or LSMW (Legacy System Migration Workbench).
  Cause:
  
  Field Definition: The selection field specified in the error message is not part of the key fields defined in the header structure of the conversion object. This means that the system expects certain fields to be key fields for processing, and the specified field does not meet this requirement.
  Configuration Issues: There may be a misconfiguration in the data migration settings or the structure of the conversion object.
  Data Mapping Errors: The mapping of fields from the source to the target structure may not be correctly defined, leading to the selection field being incorrectly identified.
  
  Solution:
  
  Check Header Structure: Review the header structure of the conversion object (object &2) to ensure that the selection field (&1) is defined as a key field. If it is not, you may need to adjust the structure or the mapping.
  Adjust Mapping: If the selection field is not supposed to be a key field, ensure that the mapping in your data migration project is correctly set up to reflect this. You may need to remove or change the selection field in your mapping.
  Consult Documentation: Refer to the SAP documentation for the specific conversion object to understand the required key fields and their definitions.
  Test with Sample Data: If possible, test the migration with a smaller set of data to isolate the issue and confirm that the changes made resolve the error.
  Seek Help from SAP Support: If the issue persists, consider reaching out to SAP support for assistance, especially if this is a critical migration process.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as LSMW, or the Data Migration Cockpit, depending on the tool you are using.
  SAP Notes: Check for any SAP Notes related to the specific conversion object or error message for additional guidance or patches.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, providing insights or solutions from other users' experiences.
  
  By following these steps, you should be able to identify the root cause of the DMCLG444 error and implement a suitable solution.