How To Fix CN406 - You cannot delete: Milestone is assigned to billing schedule

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 406

• Message text: You cannot delete: Milestone is assigned to billing schedule

What causes this issue?

The milestone is assigned to a billing schedule. When this is the case,
you cannot delete the milestone.

System Response

INCLUDE 'NA_ALLG_NOFUNKTION' OBJECT DOKU ID TX

How to fix this error?

You can delete the milestone only once you have deleted the milestone
in the billing schedule.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN406 - You cannot delete: Milestone is assigned to billing schedule ?

  The SAP error message CN406 indicates that you are trying to delete a milestone that is currently assigned to a billing schedule. This is a common issue in project management and billing processes within SAP, particularly in the context of project systems (PS) or sales and distribution (SD).
  Cause:
  The error occurs because the milestone you are attempting to delete is linked to a billing schedule. In SAP, milestones are often used to trigger billing events, and if a milestone is associated with a billing schedule, it cannot be deleted until that association is removed.
  Solution:
  To resolve this error, you can follow these steps:
  
  
  Check Billing Schedule: 
  
  Navigate to the billing schedule associated with the milestone. You can do this by going to the relevant project or sales order and checking the billing documents or schedules.
  
  
  
  Remove the Milestone from the Billing Schedule:
  
  If you have the necessary permissions, you can edit the billing schedule to remove the milestone. This may involve changing the billing plan or adjusting the billing items.
  
  
  
  Delete the Milestone:
  
  Once the milestone is no longer linked to the billing schedule, you should be able to delete it without encountering the CN406 error.
  
  
  
  Consult Documentation:
  
  If you are unsure about the steps or the implications of removing a milestone, consult your organization's SAP documentation or reach out to your SAP support team for guidance.
  
  
  
  Check for Dependencies:
  
  Ensure that there are no other dependencies or references to the milestone in other parts of the project or billing process that might prevent deletion.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CJ20N (Project Builder), CJ02 (Change Project), or VF02 (Change Billing Document) to navigate through the project and billing schedules.
  User Permissions: Ensure you have the necessary permissions to make changes to billing schedules and milestones.
  SAP Notes: Check SAP Notes for any specific patches or updates related to this error message, as there may be known issues or fixes provided by SAP.
  
  By following these steps, you should be able to resolve the CN406 error and successfully delete the milestone.