How To Fix /SAPDMC/LSMW_OBJ_040003 - Assign a source field first.

SAP Error Message - Details

• Message type: E = Error

• Message class: /SAPDMC/LSMW_OBJ_040 -

• Message number: 003

• Message text: Assign a source field first.

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPDMC/LSMW_OBJ_040003 - Assign a source field first. ?

  The SAP error message /SAPDMC/LSMW_OBJ_040003 Assign a source field first typically occurs in the context of using the Legacy System Migration Workbench (LSMW) in SAP. This error indicates that a source field has not been assigned to a target field in the mapping process, which is necessary for the data migration to proceed.
  Cause:
  The error is caused by one of the following reasons:
  
  Missing Source Field Assignment: You have not assigned a source field to the target field in the LSMW mapping.
  Incorrect Mapping Configuration: The mapping configuration may be incomplete or incorrectly set up.
  Data Structure Issues: The structure of the source data may not match the expected structure in the LSMW project.
  
  Solution:
  To resolve this error, follow these steps:
  
  
  Open LSMW Project: Go to the LSMW transaction in SAP and open the relevant project, subproject, and object.
  
  
  Check Field Mapping:
  
  Navigate to the "Field Mapping and Conversion Rules" section.
  Ensure that all target fields have corresponding source fields assigned. If any target field is missing a source field, assign the appropriate source field.
  
  
  
  Review Source Structure:
  
  Verify that the source structure is correctly defined and that the fields you are trying to map exist in the source data.
  If necessary, adjust the source structure to ensure it aligns with the target structure.
  
  
  
  Save Changes: After making the necessary assignments, save your changes.
  
  
  Test the Migration: Run a test migration to ensure that the error has been resolved and that the data is being processed correctly.
  
  
  Related Information:
  
  Documentation: Refer to the SAP Help Portal or the LSMW documentation for detailed guidance on field mapping and data migration processes.
  Transaction Codes: Familiarize yourself with relevant transaction codes such as LSMW, SE11 (Data Dictionary), and SE37 (Function Modules) for further troubleshooting.
  Community Forums: Check SAP Community forums or other user groups for similar issues and solutions shared by other users.
  
  By following these steps, you should be able to resolve the error and successfully complete your data migration using LSMW.