How To Fix CN343 - Network & is not locked; no changes possible

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 343

• Message text: Network & is not locked; no changes possible

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CN343 - Network & is not locked; no changes possible ?

  The SAP error message CN343 ("Network & is not locked; no changes possible") typically occurs in the context of project management or network planning within the SAP system, particularly in the Project System (PS) module. This error indicates that the network you are trying to modify is not locked, which means that changes cannot be made to it.
  Cause:
  
  Network Status: The network might be in a status that does not allow changes. For example, if the network is released or if it is in a status that restricts modifications.
  Locking Mechanism: SAP uses a locking mechanism to prevent simultaneous changes to the same object. If the network is not locked, it may be due to the fact that it is currently being accessed or modified by another user or process.
  Authorization Issues: The user may not have the necessary authorizations to lock the network or make changes to it.
  
  Solution:
  
  
  Check Network Status: Verify the status of the network. If it is released, you may need to set it back to a status that allows changes (e.g., "Created" or "In Process"). This can typically be done through transaction codes like CN22 (Change Network) or CN01 (Create Network).
  
  
  Lock the Network: If you have the necessary authorizations, you can manually lock the network using transaction code CN22. This will allow you to make changes to the network.
  
  
  Check for Other Users: Ensure that no other users are currently accessing or modifying the network. You can check the lock entries using transaction code SM12 to see if there are any active locks on the network.
  
  
  Authorization Check: Ensure that you have the appropriate authorizations to modify the network. You may need to contact your SAP security administrator to verify your permissions.
  
  
  Consult Documentation: If the issue persists, consult the SAP documentation or your organization's SAP support team for further assistance.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CN22 (Change Network), CN01 (Create Network), and SM12 (Display and Delete Locks).
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  User Roles: Review user roles and authorizations in the SAP system to ensure that you have the necessary permissions to perform the required actions.
  
  By following these steps, you should be able to resolve the CN343 error and make the necessary changes to the network in SAP.