How To Fix CM_SUB021 - First enter a dimension before you enter a unit of measurement

SAP Error Message - Details

• Message type: E = Error

• Message class: CM_SUB - Substance (general)

• Message number: 021

• Message text: First enter a dimension before you enter a unit of measurement

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CM_SUB021 - First enter a dimension before you enter a unit of measurement ?

  The SAP error message CM_SUB021 ("First enter a dimension before you enter a unit of measurement") typically occurs in the context of material master data or when working with certain transactions that involve units of measure and dimensions. This error indicates that the system requires a dimension to be specified before a unit of measurement can be entered.
  Cause:
  
  Missing Dimension: The primary cause of this error is that the system expects a dimension (such as length, width, height, volume, etc.) to be defined before you can specify a unit of measurement (like meters, liters, etc.).
  Incorrect Sequence of Data Entry: The user may have attempted to enter a unit of measurement without first defining the associated dimension in the relevant fields.
  
  Solution:
  To resolve the CM_SUB021 error, follow these steps:
  
  
  Enter the Dimension: Before entering the unit of measurement, ensure that you have filled in the required dimension fields. This may involve specifying the physical dimensions of the material or product you are working with.
  
  
  Check Configuration: If you are unsure about the required dimensions, check the configuration settings in the material master or the relevant transaction. Ensure that the dimensions are correctly set up in the system.
  
  
  Review Documentation: Consult the SAP documentation or help files related to the specific transaction you are using. This can provide insights into the required fields and their order.
  
  
  Data Entry Sequence: Make sure to follow the correct sequence of data entry as prescribed by the SAP system. Enter the dimension first, followed by the unit of measurement.
  
  
  Consult with SAP Support: If the issue persists after following the above steps, consider reaching out to your SAP support team or consulting the SAP community for further assistance.
  
  
  Related Information:
  
  Material Master Data: Understanding how dimensions and units of measurement are defined in the material master can help prevent this error in the future.
  Unit of Measure Configuration: Familiarize yourself with the configuration settings for units of measure in SAP, as this can impact how data is entered and validated.
  SAP Notes and Knowledge Base: Check for any relevant SAP Notes or knowledge base articles that may address this specific error or provide additional troubleshooting steps.
  
  By ensuring that dimensions are entered before units of measurement, you can avoid encountering the CM_SUB021 error in your SAP transactions.