How To Fix MDG_DT_DATA_MODEL100 - Cannot edit in development landscape; must be in Z* or Y* namespace

SAP Error Message - Details

• Message type: E = Error

• Message class: MDG_DT_DATA_MODEL - Messages for the Configuration Workbench Model Access API

• Message number: 100

• Message text: Cannot edit in development landscape; must be in Z* or Y* namespace

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message MDG_DT_DATA_MODEL100 - Cannot edit in development landscape; must be in Z* or Y* namespace ?

  The SAP error message MDG_DT_DATA_MODEL100 indicates that you are trying to edit a data model in a development landscape that is not allowed because it is not in the appropriate namespace. In SAP, objects in the development environment should typically be created in custom namespaces (usually starting with "Z" or "Y") to avoid conflicts with standard SAP objects.
  Cause:
  
  Namespace Restriction: The error occurs because the data model you are trying to edit is part of the standard SAP namespace (which does not start with "Z" or "Y"). SAP restricts modifications to standard objects in the development landscape to prevent unintended changes that could affect system stability and upgrades.
  Development Landscape: The error specifically mentions that the action must be performed in a custom namespace, which is a common practice in SAP development to ensure that custom developments do not interfere with standard SAP functionality.
  
  Solution:
  
  Use Custom Namespace: If you need to create or modify a data model, ensure that you are working within a custom namespace (Z or Y). You can create a new data model in your custom namespace.
  Copy Standard Objects: If you need to modify a standard data model, consider copying it to your custom namespace and then making the necessary changes. This can usually be done using transaction codes like SE80 (Object Navigator) or SE11 (Data Dictionary).
  Check Authorization: Ensure that you have the necessary authorizations to create or modify objects in the custom namespace.
  Consult Documentation: Review SAP documentation or consult with your SAP Basis or development team to understand the best practices for working with data models in your specific SAP environment.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that might provide additional guidance or updates related to this error message.
  Development Guidelines: Familiarize yourself with SAP's development guidelines regarding namespaces and custom developments to avoid similar issues in the future.
  Transport Management: Understand how transport requests work in SAP, especially when moving objects between different landscapes (Development, Quality Assurance, Production).
  
  By following these steps, you should be able to resolve the error and proceed with your development tasks in SAP.