How To Fix WW002 - MG reference material and MG material cannot be same

SAP Error Message - Details

• Message type: E = Error

• Message class: WW - Material group master maintenance

• Message number: 002

• Message text: MG reference material and MG material cannot be same

What causes this issue?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

System Response

How to fix this error?

Change one of the material numbers.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message WW002 - MG reference material and MG material cannot be same ?

  The SAP error message WW002, which states "MG reference material and MG material cannot be the same," typically occurs in the context of Material Management (MM) when you are trying to create or modify a material that is set up as a reference material (or a material group) and the system detects that the reference material and the material being created or modified are identical.
  Cause:
  
  Duplicate Material Assignment: The error arises when you attempt to assign a material as its own reference material. In SAP, a reference material is meant to serve as a template or standard for other materials, and it cannot reference itself.
  Configuration Issues: There may be issues in the configuration of material types or settings that allow for this incorrect assignment.
  Data Entry Error: It could also be a simple data entry mistake where the same material number is inadvertently entered in both fields.
  
  Solution:
  
  Check Material Assignment: Review the material master data to ensure that the reference material field is not set to the same material number as the material being created or modified.
  Change Reference Material: If you need to use a reference material, select a different material that serves as a valid reference.
  Review Configuration: If this error occurs frequently, it may be necessary to review the configuration settings in the material management module to ensure that the system is set up correctly to prevent such assignments.
  Data Validation: Implement validation checks in your data entry processes to prevent users from entering the same material number in both fields.
  
  Related Information:
  
  Material Types: Understanding the different material types and their configurations in SAP can help prevent this error.
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  User Training: Providing training for users on how to correctly enter material data can help reduce the occurrence of this error.
  Transaction Codes: Familiarize yourself with relevant transaction codes (like MM01 for creating materials, MM02 for changing materials) to navigate the material master data effectively.
  
  If the issue persists after following these steps, it may be beneficial to consult with your SAP support team or refer to SAP documentation for further troubleshooting.