How To Fix OO191 - Invalid namespace used

SAP Error Message - Details

• Message type: E = Error

• Message class: OO - Class Builder/API

• Message number: 191

• Message text: Invalid namespace used

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message OO191 - Invalid namespace used ?

  The SAP error message OO191 "Invalid namespace used" typically occurs when there is an issue with the namespace configuration in the ABAP development environment. This error is often related to the use of namespaces in the development objects, such as classes, interfaces, or other repository objects.
  Cause:
  
  Invalid Namespace: The namespace used in the object does not conform to the naming conventions or is not recognized by the system.
  Missing Namespace Configuration: The namespace may not be properly defined in the system settings.
  Transport Issues: If the object was transported from another system, the namespace might not exist in the target system.
  Development Class Issues: The development class (package) associated with the object may not be correctly set up or may not allow the use of certain namespaces.
  
  Solution:
  
  
  Check Namespace Configuration:
  
  Go to transaction SE03 (Transport Organizer Tools) and check the namespace settings.
  Ensure that the namespace is correctly defined and active.
  
  
  
  Review Object Naming:
  
  Ensure that the object (class, interface, etc.) is using a valid namespace. The namespace should follow the format defined by SAP (e.g., /Z or /Y for custom namespaces).
  
  
  
  Adjust Development Class:
  
  If the object is part of a development class, check the settings of that class in transaction SE80 or SE21. Ensure that it allows the use of the specified namespace.
  
  
  
  Transport Request:
  
  If the object was transported, ensure that the transport request was successful and that the namespace exists in the target system.
  
  
  
  Create or Modify Namespace:
  
  If necessary, create a new namespace or modify the existing one to ensure it meets the requirements.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or help resources for specific guidelines on namespace usage and configuration.
  
  
  
  Related Information:
  
  Namespace Naming Conventions: SAP has specific conventions for naming namespaces, which typically start with a forward slash followed by a letter (e.g., /Z or /Y).
  Development Guidelines: Follow SAP's best practices for development, including proper use of namespaces to avoid conflicts and ensure maintainability.
  SAP Notes: Check for any relevant SAP Notes that may address specific issues related to namespaces and the OO191 error.
  
  If the issue persists after following these steps, it may be beneficial to consult with your SAP Basis or development team for further assistance.