How To Fix CN623 - Standard network contains & loop(s)

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 623

• Message text: Standard network contains & loop(s)

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CN623 - Standard network contains & loop(s) ?

  The SAP error message CN623, which states "Standard network contains & loop(s)," typically occurs in the context of project management and network planning within SAP. This error indicates that there are circular dependencies or loops in the network structure of a project, which can prevent the system from processing the project correctly.
  Cause:
  
  Circular Dependencies: The most common cause of this error is the presence of circular dependencies in the network activities. This means that one or more activities are linked in such a way that they create a loop, making it impossible for the system to determine a valid sequence of execution.
  Incorrect Relationships: Incorrectly defined relationships (predecessors and successors) between activities can lead to loops.
  Multiple Paths: If there are multiple paths that lead back to the same activity, it can create a loop.
  
  Solution:
  
  Review Network Activities: Check the network activities for any circular dependencies. You can do this by reviewing the relationships between activities in the project.
  Adjust Relationships: Modify the relationships between activities to eliminate any loops. Ensure that each activity has a clear predecessor and successor without creating a cycle.
  Use the Network Diagram: Utilize the network diagram feature in SAP to visualize the activities and their relationships. This can help identify where the loops are occurring.
  Check for Errors: Use transaction codes like CN22 (Change Network) or CN41 (Network Overview) to analyze the network and identify any inconsistencies or errors in the activity relationships.
  Recreate the Network: If the network is too complex or if the loops are difficult to identify, consider recreating the network from scratch, ensuring that the relationships are defined correctly from the beginning.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CN22 (Change Network), CN41 (Network Overview), and CN42 (Display Network) to manage and analyze networks effectively.
  Documentation: Refer to SAP documentation or help files for detailed guidance on network planning and management.
  SAP Notes: Check for any SAP Notes related to this error message, as they may provide additional insights or patches that could resolve the issue.
  Training: Consider training sessions or workshops on SAP Project System (PS) to better understand network planning and avoid such issues in the future.
  
  By following these steps, you should be able to resolve the CN623 error and ensure that your project network is structured correctly.