How To Fix WM166 - Variant &2 of generic material &1 already assigned in module &3

WM166 - Overview

• Message type: E = Error

• Message class: WM - IS-R Assortments

• Message number: 166

• Message text: Variant &2 of generic material &1 already assigned in module &3

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.

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WM166 - Details

• The SAP error message WM166 indicates that a variant of a generic material has already been assigned in a specific module. This typically occurs in the Warehouse Management (WM) module when you are trying to assign a variant of a generic material that is already in use or assigned elsewhere in the system.
  
  Cause:
  
  Duplicate Assignment: The specific variant of the generic material is already assigned to another location, storage type, or process within the WM module.
  
  Configuration Issues: There may be configuration settings that prevent the assignment of the same variant to multiple locations or processes.
  Data Integrity: The system may have integrity checks that prevent the same variant from being assigned to multiple transactions or locations to avoid confusion and errors in inventory management.
  
  
  Solution:
  
  Check Existing Assignments: Review the current assignments of the generic material variant in the system. You can do this by navigating to the relevant transaction codes (like WM or