How To Fix FDT_CORE255 - Applications at SAP must not be created in customer namespace

SAP Error Message - Details

• Message type: E = Error

• Message class: FDT_CORE - Formula & Derivation Tool: Core

• Message number: 255

• Message text: Applications at SAP must not be created in customer namespace

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message FDT_CORE255 - Applications at SAP must not be created in customer namespace ?

  The SAP error message FDT_CORE255 indicates that applications in the SAP system should not be created in the customer namespace. This is a restriction imposed by SAP to ensure that standard applications and functionalities remain intact and are not overridden or modified in a way that could lead to inconsistencies or issues during upgrades or support.
  Cause:
  The error typically arises when a user attempts to create or modify an application in a customer namespace (usually starting with "Z" or "Y"). SAP reserves certain namespaces for its own development and applications, and creating custom applications in these areas can lead to conflicts with standard SAP applications.
  Solution:
  To resolve this error, you should follow these steps:
  
  
  Use the Correct Namespace: Ensure that you are creating your applications in the appropriate customer namespace. Custom developments should be done in namespaces that are designated for customer use (usually starting with "Z" or "Y").
  
  
  Check Application Type: If you are trying to create a new application, verify that it is indeed intended to be a custom application. If it is meant to be a standard application, consider using the existing standard applications provided by SAP.
  
  
  Review Documentation: Consult the SAP documentation or guidelines regarding application development to ensure compliance with SAP's best practices.
  
  
  Consult SAP Notes: Check for any relevant SAP Notes that might provide additional context or solutions related to this error message.
  
  
  Contact SAP Support: If you are unsure about the namespace or the implications of your development, consider reaching out to SAP support for guidance.
  
  
  Related Information:
  
  Namespaces in SAP: SAP uses namespaces to differentiate between standard SAP objects and customer-specific objects. The standard namespace is reserved for SAP's own developments, while customer namespaces are for custom developments.
  Development Guidelines: SAP provides guidelines for development practices, including naming conventions and best practices for creating custom applications.
  Upgrades and Support: Modifications in the customer namespace can complicate system upgrades and support, as they may conflict with standard SAP functionalities.
  
  By adhering to these guidelines and ensuring that your developments are in the correct namespace, you can avoid encountering the FDT_CORE255 error in the future.