How To Fix TN120 - Predecessor &1 of &2 does not exist

SAP Error Message - Details

• Message type: E = Error

• Message class: TN - Support Package Manager (SPAM) Messages

• Message number: 120

• Message text: Predecessor &1 of &2 does not exist

What causes this issue?

The queue is not consistent because the predecessor &V1& of &V2& is
missing.

System Response

The queue cannot be confirmed.

How to fix this error?

&V1& has probably not yet been downloaded to your system.
Request the Support Package in SAPNet - R/3 Frontend and load it into
your system.
Then confirm the queue.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message TN120 - Predecessor &1 of &2 does not exist ?

  The SAP error message TN120, which states "Predecessor &1 of &2 does not exist," typically occurs in the context of project management or production planning when there is an issue with task dependencies or relationships between different elements (like activities, tasks, or orders) in a project or production order.
  Cause:
  
  
  Missing Predecessor: The predecessor task or activity (denoted as &1) that is supposed to be linked to the current task or activity (denoted as &2) does not exist in the system. This could be due to:
  
  The predecessor was deleted or not created.
  There is a typo or incorrect entry in the predecessor field.
  The predecessor is in a different project or order that is not accessible.
  
  
  
  Data Inconsistency: There may be inconsistencies in the data, such as incorrect configuration or missing entries in the relevant tables.
  
  
  Authorization Issues: Sometimes, the user may not have the necessary authorizations to view or access the predecessor task.
  
  
  Solution:
  
  
  Check Predecessor Entry: Verify that the predecessor task or activity exists in the system. You can do this by:
  
  Navigating to the relevant project or order and checking the list of tasks or activities.
  Ensuring that the predecessor ID is correctly entered without any typos.
  
  
  
  Create or Restore Predecessor: If the predecessor does not exist, you may need to create it or restore it if it was deleted. Ensure that all necessary details are filled in correctly.
  
  
  Review Task Relationships: Check the relationships between tasks to ensure that they are set up correctly. You may need to adjust the dependencies if they are incorrectly configured.
  
  
  Authorization Check: Ensure that you have the necessary authorizations to view and manage the predecessor tasks. If not, contact your system administrator to grant the required permissions.
  
  
  Consult Documentation: If the issue persists, refer to SAP documentation or consult with your SAP support team for further assistance.
  
  
  Related Information:
  
  Transaction Codes: You may use transaction codes like CJ20N (Project Builder) or CO02 (Change Production Order) to check and manage project or order details.
  SAP Notes: Check for any relevant SAP Notes that might address this specific error or provide additional troubleshooting steps.
  System Logs: Review system logs for any additional error messages or warnings that could provide more context about the issue.
  
  By following these steps, you should be able to identify and resolve the cause of the TN120 error in SAP.