How To Fix CN457 - Scheduling with subnetworks not allowed

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 457

• Message text: Scheduling with subnetworks not allowed

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 CN457 - Scheduling with subnetworks not allowed ?

  The SAP error message CN457 ("Scheduling with subnetworks not allowed") typically occurs in the context of project management and network scheduling within SAP. This error indicates that the system has encountered a situation where it is trying to schedule a project or network that contains subnetworks, which is not permitted in the current configuration or context.
  Cause:
  
  Subnetwork Usage: The error arises when you attempt to schedule a project that includes subnetworks. In SAP, subnetworks are used to break down larger networks into smaller, manageable parts, but scheduling them together with the main network is not allowed.
  Network Type: The type of network you are working with may not support scheduling with subnetworks.
  Configuration Settings: There may be specific configuration settings in your SAP system that restrict the scheduling of subnetworks.
  
  Solution:
  
  Check Network Structure: Review the network structure to ensure that you are not including subnetworks in the scheduling process. If subnetworks are present, consider scheduling them separately.
  Adjust Scheduling Parameters: If you need to schedule subnetworks, you may need to adjust your scheduling parameters or settings to allow for this. Consult with your SAP administrator or refer to the configuration documentation.
  Use Alternative Scheduling Methods: If the project requires the use of subnetworks, consider using alternative methods for scheduling that do not involve direct scheduling of the main network with subnetworks.
  Consult Documentation: Refer to SAP documentation or help resources for specific guidelines on handling subnetworks and scheduling in your version of SAP.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP frequently updates its system with notes that may address specific errors.
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CN22 (Change Network) or CJ20N (Project Builder) to manage networks and projects effectively.
  User Roles and Permissions: Ensure that you have the necessary permissions to perform scheduling actions within the project management module.
  Training and Support: If you are frequently encountering this error, consider seeking additional training on SAP project management or consulting with an SAP expert for tailored support.
  
  By following these steps, you should be able to resolve the CN457 error and effectively manage your project scheduling within SAP.