How To Fix DMC_RT_MSG129 - Sheet &1 / Field &2 unknown

SAP Error Message - Details

• Message type: E = Error

• Message class: DMC_RT_MSG - DMC: Runtime Object Messages

• Message number: 129

• Message text: Sheet &1 / Field &2 unknown

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.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message DMC_RT_MSG129 - Sheet &1 / Field &2 unknown ?

  The SAP error message DMC_RT_MSG129, which states "Sheet &1 / Field &2 unknown," typically occurs in the context of data migration or data management processes, particularly when using tools like SAP Data Migration Cockpit (DMC) or SAP S/4HANA Migration Cockpit. This error indicates that the system is unable to recognize a specified sheet or field in the data file being processed.
  
  Cause:
  
  Incorrect Sheet Name: The specified sheet name in the data file does not match any of the expected sheet names defined in the migration template.
  Missing Field: The specified field does not exist in the defined structure of the migration template or is misspelled.
  File Format Issues: The data file may not be in the correct format (e.g., Excel, CSV) or may have formatting issues that prevent proper reading.
  Template Version Mismatch: The template being used may not be compatible with the version of the migration tool or the target system.
  Data Mapping Issues: