How To Fix MA028 - Not possible to change unit to "blank"

SAP Error Message - Details

• Message type: E = Error

• Message class: MA - Sales and Operations Planning

• Message number: 028

• Message text: Not possible to change unit to "blank"

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.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message MA028 - Not possible to change unit to "blank" ?

  The SAP error message MA028, which states "Not possible to change unit to 'blank'," typically occurs in the context of material master data or inventory management when there is an attempt to change the unit of measure (UoM) for a material to a blank value. This is not allowed because a material must always have a defined unit of measure.
  Cause:
  
  Invalid Input: The user may have inadvertently left the unit of measure field blank when trying to update material data.
  System Configuration: There may be a configuration issue or a custom program that is incorrectly handling unit of measure changes.
  Data Integrity: The system enforces data integrity rules that prevent the unit of measure from being set to a blank value.
  
  Solution:
  
  Check Input: Ensure that the unit of measure field is not left blank. Enter a valid unit of measure that is defined in the system.
  Review Changes: If you are using a program or transaction to update material data, review the logic to ensure it does not attempt to set the unit of measure to blank.
  Material Master Data: If you are working with the material master, navigate to the relevant transaction (e.g., MM02 for changing material master data) and ensure that all required fields, including the unit of measure, are filled out correctly.
  Consult Documentation: Refer to SAP documentation or help resources for guidance on the specific transaction or process you are using.
  Contact Support: If the issue persists and you cannot identify the cause, consider reaching out to your SAP support team or consulting with an SAP expert for further assistance.
  
  Related Information:
  
  Transaction Codes: Common transaction codes related to material management include MM01 (Create Material), MM02 (Change Material), and MM03 (Display Material).
  Unit of Measure Configuration: Review the configuration settings for units of measure in the SAP system, which can be found in the customizing settings under Logistics > Material Management > Basic Settings > Units of Measure.
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional troubleshooting steps.
  
  By following these steps, you should be able to resolve the MA028 error and successfully update the material data as needed.