How To Fix M2688 - Error for self-defined units

SAP Error Message - Details

• Message type: E = Error

• Message class: M2 - LIS: Generating and updating info structures

• Message number: 688

• Message text: Error for self-defined units

What causes this issue?

In a communication structure, two or more units are not allowed to use
the same data element.

System Response

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

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message M2688 - Error for self-defined units ?

  The SAP error message M2688 typically indicates an issue related to self-defined units of measure in the system. This error can occur when there is a problem with the configuration or usage of custom units of measure in material management or inventory processes.
  Cause:
  
  Incorrect Configuration: The self-defined unit of measure may not be properly configured in the system. This includes issues with the unit's definition, conversion factors, or its assignment to materials.
  Missing Master Data: The material master data may not have the necessary information related to the custom unit of measure.
  Inconsistent Data: There may be inconsistencies in the data related to the unit of measure, such as missing entries in the unit of measure tables.
  Usage in Transactions: The custom unit of measure may be used in transactions where it is not valid or not allowed.
  
  Solution:
  
  
  Check Configuration:
  
  Go to the configuration settings for units of measure in SAP (Transaction Code: OME1 for defining units of measure).
  Ensure that the self-defined unit of measure is correctly set up, including its conversion factors and relationships with other units.
  
  
  
  Review Material Master Data:
  
  Use Transaction Code MM03 to check the material master data for the materials using the self-defined unit of measure.
  Ensure that the unit of measure is correctly assigned in the material master.
  
  
  
  Validate Unit of Measure Tables:
  
  Check the relevant tables (e.g., T006 for units of measure) to ensure that the self-defined unit is present and correctly defined.
  Look for any inconsistencies or missing entries.
  
  
  
  Test Transactions:
  
  Try to replicate the error by performing the same transaction that caused the error. This can help identify if the issue is with specific materials or transactions.
  
  
  
  Consult Documentation:
  
  Review SAP documentation or help resources for any specific notes related to the error message M2688.
  
  
  
  Seek Support:
  
  If the issue persists, consider reaching out to your SAP support team or consulting SAP Notes for further assistance.
  
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error message or provide additional troubleshooting steps.
  Unit of Measure Documentation: Familiarize yourself with SAP's documentation on units of measure, as it can provide insights into best practices for defining and using custom units.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By following these steps, you should be able to identify and resolve the issue related to the M2688 error message in SAP.