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

CJ820 - Overview

• 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.

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 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