How To Fix /SAPAPO/MAT831 - Only one unit of measure category can be set to A or B

SAP Error Message - Details

• Message type: E = Error

• Message class: /SAPAPO/MAT -

• Message number: 831

• Message text: Only one unit of measure category can be set to A or B

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPAPO/MAT831 - Only one unit of measure category can be set to A or B ?

  The SAP error message /SAPAPO/MAT831 indicates that there is an issue with the unit of measure (UoM) configuration for a material in the Advanced Planning and Optimization (APO) module. Specifically, it states that only one unit of measure category can be set to "A" (base unit of measure) or "B" (alternative unit of measure) for a given material.
  Cause:
  This error typically arises when:
  
  Multiple UoM Categories: You have defined multiple units of measure for a material, and more than one of them is incorrectly set to category "A" or "B".
  Configuration Error: There may be a configuration error in the material master data where the unit of measure categories are not set up correctly.
  Data Inconsistency: There could be inconsistencies in the data between the material master in SAP ERP and the APO system.
  
  Solution:
  To resolve this error, you can follow these steps:
  
  
  Check Material Master Data:
  
  Go to the material master data in the SAP GUI (transaction code MM03).
  Check the units of measure assigned to the material under the "Basic Data" or "Sales Org. Data" views.
  Ensure that only one unit of measure is assigned to category "A" and only one to category "B".
  
  
  
  Adjust UoM Categories:
  
  If you find multiple units of measure assigned to the same category, you will need to adjust the settings. You can do this by:
  
  Changing the category of one of the units of measure to "C" (alternative unit of measure) or another appropriate category.
  Deleting or deactivating the unnecessary unit of measure.
  
  
  
  
  
  Synchronize Data:
  
  If the material master data is maintained in both SAP ERP and APO, ensure that the data is synchronized. You may need to run the relevant data transfer or synchronization jobs to ensure consistency.
  
  
  
  Check Customizing Settings:
  
  If you have custom settings for units of measure, check the customizing settings in the SAP system (transaction code SPRO) to ensure that they are correctly configured.
  
  
  
  Testing:
  
  After making the necessary changes, test the material in the APO system to ensure that the error no longer occurs.
  
  
  
  Related Information:
  
  Unit of Measure Categories: Understanding the different unit of measure categories (A, B, C, etc.) is crucial for proper material management in SAP.
  Material Master Data: Familiarize yourself with the structure and importance of material master data in both SAP ERP and APO.
  SAP Notes: Check for any relevant SAP Notes that may provide additional guidance or fixes related to this error message.
  
  If the issue persists after following these steps, consider reaching out to your SAP support team or consulting the SAP community for further assistance.