How To Fix CN821 - This relationship already exists

CN821 - Overview

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 821

• Message text: This relationship already exists

What causes this issue?

You have maintained a relationship that already exists.

System Response

INCLUDE 'NA_ALLG_NOVERARBEITUNG' OBJECT DOKU ID TX

How to fix this error?

Check what you have entered for the relationship. Make any necessary
changes.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN821 - This relationship already exists ?

  The SAP error message CN821 ("This relationship already exists") typically occurs in the context of project management or network planning within the SAP system, particularly when dealing with relationships between activities in a project or network.
  
  Cause:
  The error message CN821 is triggered when you attempt to create a relationship (such as a predecessor or successor relationship) between two activities or tasks that already have an existing relationship defined in the system. This can happen due to:
  
  Duplicate Entry: You are trying to create a relationship that already exists.
  Incorrect Data Entry: There may be a misunderstanding of the relationships that are already established.
  System Constraints: The system may have constraints that prevent the creation of multiple relationships of the same type between the same activities.
  
  
  Solution:
  To resolve the CN821 error, you can take the following steps:
  
  
  Check Existing Relationships:
  
  Navigate to the project or network where the error occurred.
  Review the existing relationships between the activities to confirm