How To Fix CJ820 - The external key is not compatible with the internal key

SAP Error Message - Details

• Message type: E = Error

• Message class: CJ - Project master data and structure

• Message number: 820

• Message text: The external key is not compatible with the internal key

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CJ820 - The external key is not compatible with the internal key ?

  The SAP error message CJ820, which states "The external key is not compatible with the internal key," typically occurs in the context of project management and controlling within SAP, particularly when dealing with project definitions, WBS (Work Breakdown Structure) elements, or network activities.
  Cause:
  This error usually arises due to one of the following reasons:
  
  
  Mismatch of Key Formats: The external key (which could be a project number or WBS element) does not match the expected format or structure of the internal key used by SAP. This can happen if the external key is incorrectly formatted or if it does not exist in the system.
  
  
  Data Entry Errors: There may be typographical errors in the external key being entered, leading to a mismatch.
  
  
  Configuration Issues: The system configuration may not be set up to recognize the external key, especially if there are customizations or specific settings in place.
  
  
  Project Status: The project or WBS element may be in a status that does not allow for the operation being attempted, such as being locked or archived.
  
  
  Solution:
  To resolve the CJ820 error, you can take the following steps:
  
  
  Verify the External Key: Check the external key you are trying to use. Ensure that it is correctly formatted and exists in the system. You can do this by searching for the project or WBS element in the relevant transaction (e.g., CJ20N for project management).
  
  
  Check for Typographical Errors: Ensure that there are no typos in the external key you are entering. Double-check for any extra spaces or incorrect characters.
  
  
  Review Configuration Settings: If you have access to configuration settings, review the settings related to project management and WBS elements to ensure that they are correctly set up to recognize the external keys.
  
  
  Check Project Status: Ensure that the project or WBS element is in an appropriate status for the operation you are trying to perform. If it is locked or archived, you may need to unlock or reactivate it.
  
  
  Consult Documentation: Refer to SAP documentation or help resources for specific details related to the error message and its context.
  
  
  Contact SAP Support: If the issue persists after checking the above points, consider reaching out to your SAP support team or SAP directly for further assistance.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CJ20N (Project Builder), CJ02 (Change Project), and CJ03 (Display Project) to manage projects and WBS elements effectively.
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  User Authorization: Ensure that you have the necessary authorizations to perform the actions related to the project or WBS element.
  
  By following these steps, you should be able to identify and resolve the cause of the CJ820 error in SAP.