How To Fix MD766 - WBS BOM for reference production lot & already exists

SAP Error Message - Details

• Message type: E = Error

• Message class: MD - Material Requirements Planning (MRP)

• Message number: 766

• Message text: WBS BOM for reference production lot & already exists

What causes this issue?

The reference production lot & already has a work breakdown structure
BOM (WBS BOM). If you change or delete the <DS:DE.PL_PLPVL>reference
production lot</>, the WBS BOM of the reference production lot is no
longer used. Instead, the system uses the WBS BOM of the production
lot, if available, or the WBS BOM of the newly specified reference
production lot - if you specify another reference production lot.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MD766 - WBS BOM for reference production lot & already exists ?

  The SAP error message MD766 indicates that there is an issue with the Bill of Materials (BOM) for a Work Breakdown Structure (WBS) element in relation to a reference production lot. Specifically, it suggests that a BOM for the specified WBS element already exists, which is causing a conflict when trying to create or modify it.
  Cause:
  
  Existing BOM: The primary cause of this error is that a BOM for the specified WBS element already exists in the system. SAP does not allow the creation of duplicate BOMs for the same WBS element.
  Incorrect Data Entry: There may be a mistake in the data entry, such as using the wrong WBS element or production lot.
  System Configuration: There could be configuration settings in the SAP system that enforce strict rules regarding BOM creation and management.
  
  Solution:
  
  
  Check Existing BOMs: 
  
  Use transaction code CS03 (Display BOM) to check if a BOM already exists for the specified WBS element. If it does, you may need to modify or delete the existing BOM instead of creating a new one.
  
  
  
  Modify Existing BOM: 
  
  If the existing BOM needs to be updated, you can use transaction code CS02 (Change BOM) to make the necessary changes to the existing BOM.
  
  
  
  Use Correct WBS Element: 
  
  Ensure that you are using the correct WBS element and production lot when attempting to create or modify the BOM. Double-check the input data for accuracy.
  
  
  
  Consult Documentation: 
  
  Review any relevant documentation or guidelines within your organization regarding BOM management and WBS elements to ensure compliance with internal processes.
  
  
  
  SAP Notes and Support: 
  
  If the issue persists, consider checking SAP Notes for any known issues or patches related to this error. You can also reach out to SAP support for further assistance.
  
  
  
  Related Information:
  
  
  Transaction Codes:
  
  CS01: Create BOM
  CS02: Change BOM
  CS03: Display BOM
  CST01: Create WBS BOM
  CST02: Change WBS BOM
  CST03: Display WBS BOM
  
  
  
  BOM Types: Understand the different types of BOMs (e.g., production BOM, WBS BOM) and their specific uses within your organization.
  
  
  WBS Elements: Familiarize yourself with how WBS elements are structured and used in project management within SAP.
  
  
  By following these steps, you should be able to resolve the MD766 error and manage your BOMs effectively.