How To Fix CN624 - Standard network contains loops and cannot be scheduled

CN624 - Overview

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 624

• Message text: Standard network contains loops and cannot be scheduled

What causes this issue?

The standard network cannot be scheduled because the relationships to
activities have created a loop.

System Response

INCLUDE 'NA_ALLG_NOFUNKTION' OBJECT DOKU ID TX

How to fix this error?

RESET N1
Call up the network structure graphic.
Select the menu options <LS>Edit -> Functions -> Loop analysis ->
Execute</>.
The relationships causing the loop are highlighted.
Choose new relationships between activities so the loop no longer
exists.
Select the menu options <LS>Edit -> Functions -> Loop analysis ->
Execute</>.
The relationships are no longer highlighted.

Error message extract from SAP system. Copyright SAP SE.

CN624 - Details

• The SAP error message CN624 indicates that there are loops in the standard network of a project, which prevents the scheduling of the project. This error typically arises in the context of project management within SAP, particularly when using the Project System (PS) module.
  
  Cause:
  The primary cause of the CN624 error is the presence of circular dependencies in the network activities. This can happen due to:
  
  Incorrect Activity Relationships: Activities may be incorrectly linked, creating a situation where an activity depends on itself, either directly or indirectly.
  Missing or Incorrectly Defined Milestones: If milestones are not properly defined or linked, it can lead to circular dependencies.
  Manual Changes: Manual adjustments to the network structure that inadvertently create loops.
  
  
  Solution:
  To resolve the CN624 error, follow these steps:
  
  
  Check Activity Relationships:
  
  Go to the network in question and review the relationships between activities.
  Ensure that there are no circular dependencies. Each activity should have a clear predecessor and successor.
  
  
  
  Use the