How To Fix /SAPDMC/LSMW304 - Define the identification of the source structures first

SAP Error Message - Details

• Message type: E = Error

• Message class: /SAPDMC/LSMW -

• Message number: 304

• Message text: Define the identification of the source structures first

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPDMC/LSMW304 - Define the identification of the source structures first ?

  The SAP error message /SAPDMC/LSMW304 indicates that there is an issue with the configuration of the Legacy System Migration Workbench (LSMW) in SAP. Specifically, it suggests that the identification of the source structures has not been defined before attempting to execute a migration project.
  Cause:
  The error typically occurs when:
  
  The source structures for the data migration have not been defined in the LSMW project.
  The project or subproject is not properly set up to include the necessary source structure definitions.
  There may be a missing or incorrect mapping between the source and target structures.
  
  Solution:
  To resolve this error, follow these steps:
  
  
  Define Source Structures:
  
  Go to the LSMW transaction (LSMW).
  Select the appropriate project and subproject.
  Navigate to the "Maintain Source Structures" option.
  Define the source structures that you will be using for the data migration. Ensure that you specify the correct structure names and attributes.
  
  
  
  Check Mapping:
  
  After defining the source structures, ensure that you have mapped them correctly to the target structures.
  Go to the "Maintain Field Mapping and Conversion Rules" section and verify that the fields from the source structures are correctly mapped to the corresponding fields in the target structure.
  
  
  
  Save Changes:
  
  After making the necessary changes, save your configuration.
  You may also want to activate the project if required.
  
  
  
  Re-run the Migration:
  
  Once the source structures are defined and mapped, try to execute the migration process again.
  
  
  
  Related Information:
  
  Documentation: Refer to the SAP Help Portal or the LSMW documentation for detailed guidance on setting up LSMW projects and defining source structures.
  Transaction Codes: Familiarize yourself with relevant transaction codes such as LSMW, SE11 (Data Dictionary), and SE37 (Function Modules) for further troubleshooting.
  Error Logs: Check the error logs for any additional messages that may provide more context about the issue.
  
  By following these steps, you should be able to resolve the /SAPDMC/LSMW304 error and successfully define the identification of the source structures in your LSMW project.