How To Fix /IWFND/CM_MGW028 - Namespace &1 not allowed; use 'Y' or 'Z' as first character in the prefix

SAP Error Message - Details

• Message type: E = Error

• Message class: /IWFND/CM_MGW -

• Message number: 028

• Message text: Namespace &1 not allowed; use 'Y' or 'Z' as first character in the prefix

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /IWFND/CM_MGW028 - Namespace &1 not allowed; use 'Y' or 'Z' as first character in the prefix ?

  The SAP error message /IWFND/CM_MGW028 indicates that there is an issue with the namespace used in your OData service. Specifically, the error states that the namespace prefix must start with either 'Y' or 'Z'. In SAP, custom namespaces are typically prefixed with 'Y' or 'Z' to distinguish them from standard SAP namespaces.
  Cause:
  The error occurs when you attempt to create or register an OData service with a namespace that does not conform to the naming convention. This usually happens when:
  
  The namespace prefix does not start with 'Y' or 'Z'.
  You are trying to use a standard SAP namespace or an invalid custom namespace.
  
  Solution:
  To resolve this error, you need to ensure that the namespace you are using for your OData service starts with 'Y' or 'Z'. Here are the steps to fix the issue:
  
  
  Check the Namespace: Review the namespace you are using in your OData service definition. Make sure it starts with 'Y' or 'Z'.
  
  
  Modify the Namespace: If the namespace does not conform to the naming convention, you will need to change it. You can do this in the service definition or in the relevant configuration settings.
  
  
  Re-register the Service: After modifying the namespace, re-register the OData service in the SAP Gateway using transaction code /IWFND/MAINT_SERVICE.
  
  
  Test the Service: Once the service is registered with the correct namespace, test it to ensure that it is functioning as expected.
  
  
  Related Information:
  
  Namespaces in SAP: In SAP, namespaces are used to avoid naming conflicts between standard SAP objects and custom developments. Custom objects should always use 'Y' or 'Z' as prefixes.
  OData Services: OData (Open Data Protocol) is a standard protocol for building and consuming RESTful APIs. In SAP, OData services are often used to expose business data and functionality.
  SAP Gateway: The SAP Gateway is a technology that enables the connection of devices, environments, and platforms to SAP systems. It allows for the creation of OData services.
  
  By following these steps and ensuring that your namespace adheres to the required conventions, you should be able to resolve the error and successfully register your OData service.