How To Fix CN651 - Select relationship first

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 651

• Message text: Select relationship first

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CN651 - Select relationship first ?

  The SAP error message CN651 ("Select relationship first") typically occurs in the context of project management or network planning within the SAP system, particularly when working with the Project System (PS) module. This error indicates that the system expects you to select a relationship before performing a certain action, such as assigning or modifying activities in a project.
  Cause:
  The error is usually triggered when:
  
  You attempt to perform an operation (like copying, deleting, or changing) on a network or activity without first selecting a relationship.
  The system requires a specific relationship (like finish-to-start, start-to-start, etc.) to be defined between activities before proceeding with the operation.
  
  Solution:
  To resolve the CN651 error, follow these steps:
  
  
  Select the Relationship: 
  
  Before performing the action that triggered the error, ensure that you have selected the appropriate relationship between the activities or tasks in your project.
  You can do this by navigating to the relevant screen where you manage relationships (e.g., the "Network" or "Activity" screen) and selecting the relationship type you want to work with.
  
  
  
  Check Activity Settings:
  
  Ensure that the activities you are trying to link or modify are correctly set up and that there are no missing dependencies or relationships.
  
  
  
  Review Project Structure:
  
  Make sure that the project structure is correctly defined and that all necessary relationships are established. You may need to go back and define relationships for activities that are missing them.
  
  
  
  Consult Documentation:
  
  If you are unsure about how to select relationships or what types of relationships are available, refer to the SAP documentation or help resources specific to the Project System module.
  
  
  
  User Permissions:
  
  Ensure that you have the necessary permissions to modify relationships in the project. Sometimes, restrictions can lead to errors when trying to perform certain actions.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CJ20N (Project Builder) or CN22 (Change Network) where you can manage project activities and relationships.
  SAP Notes: Check for any SAP Notes related to this error message for additional troubleshooting steps or patches that may address known issues.
  Training and Support: If you continue to experience issues, consider reaching out to your SAP support team or consulting with a colleague who has experience with the Project System module.
  
  By following these steps, you should be able to resolve the CN651 error and continue working with your project in SAP.