How To Fix C%021 - Enter a unique reference object

SAP Error Message - Details

• Message type: E = Error

• Message class: C% -

• Message number: 021

• Message text: Enter a unique reference object

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 C%021 - Enter a unique reference object ?

  The SAP error message C%021, which states "Enter a unique reference object," typically occurs in the context of creating or managing cost objects, such as internal orders, projects, or cost centers. This error indicates that the system requires a unique identifier for the reference object you are trying to enter, but the value provided is either duplicated or not valid.
  Causes:
  
  Duplicate Entry: The reference object you are trying to enter already exists in the system, and SAP requires a unique identifier.
  Incorrect Input: The input format may not meet the system's requirements, leading to the inability to recognize it as a unique object.
  
  Configuration Issues: There may be configuration settings in the SAP system that enforce uniqueness for certain fields or objects.
  
  Solutions:
  
  Check Existing Objects: Verify if the reference object you are trying to enter already exists in the system. You can do this by searching for the object in the relevant transaction or