How To Fix CN453 - Meilestone number &1 can no longer be changed in &2

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 453

• Message text: Meilestone number &1 can no longer be changed in &2

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.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN453 - Meilestone number &1 can no longer be changed in &2 ?

  The SAP error message CN453 indicates that a milestone number (in this case, &1) cannot be changed in the specified object (in this case, &2). This error typically occurs in the context of project management or project systems (PS) within SAP, particularly when dealing with project milestones in a project structure.
  Cause:
  The error CN453 usually arises due to one of the following reasons:
  
  Milestone Status: The milestone may have already been completed or confirmed, which prevents any changes to its details.
  Project Structure: The milestone might be part of a project structure that has been locked or is in a status that does not allow changes.
  Authorization Issues: The user may not have the necessary authorizations to make changes to the milestone.
  Dependencies: There may be dependencies or relationships with other project elements that restrict changes to the milestone.
  
  Solution:
  To resolve the CN453 error, you can take the following steps:
  
  Check Milestone Status: Verify the status of the milestone. If it is completed or confirmed, you may need to reverse that status before making changes.
  Review Project Structure: Ensure that the project structure allows for changes. If the project is locked or in a specific status, you may need to unlock it or change its status.
  Authorization Check: Confirm that you have the necessary authorizations to modify the milestone. If not, contact your SAP administrator to obtain the required permissions.
  Dependencies Review: Investigate any dependencies or relationships that may be preventing changes. You may need to adjust related elements before modifying the milestone.
  Consult Documentation: Refer to SAP documentation or help resources for specific guidelines related to milestones in your version of SAP.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CJ20N (Project Builder) or CJ02 (Change Project) to navigate and manage project milestones.
  SAP Notes: Check for any SAP Notes related to error CN453 for additional insights or patches that may address the issue.
  User Forums: Engage with SAP community forums or support channels for shared experiences and solutions from other users who may have encountered the same error.
  
  By following these steps, you should be able to identify the cause of the CN453 error and implement a suitable solution.