How To Fix BOS01128 - Subpackage number cannot be changed for outline level &1

BOS01128 - Overview

• Message type: E = Error

• Message class: BOS01 - Customer BOS Processing

• Message number: 128

• Message text: Subpackage number cannot be changed for outline level &1

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.

BOS01128 - Details

• The SAP error message BOS01128, which states "Subpackage number cannot be changed for outline level &1," typically occurs in the context of project management or when dealing with structured data in SAP, such as in the Project System (PS) or other modules that utilize hierarchical structures.
  
  Cause:
  This error usually arises when there is an attempt to change the subpackage number of a project or a structured element that is already defined in the system. The subpackage number is a unique identifier for a specific outline level in a project structure, and once it is set, it cannot be modified. This restriction is in place to maintain data integrity and consistency within the project structure.
  
  Solution:
  To resolve this error, consider the following steps:
  
  
  Check the Outline Level: Verify the outline level (indicated by &1 in the error message) that you are trying to modify. Ensure that you are not attempting to change the subpackage