How To Fix /IWBEP/CM_MGW_RT129 - Class element ID '&1' does not exist in class '&2'

SAP Error Message - Details

• Message type: E = Error

• Message class: /IWBEP/CM_MGW_RT -

• Message number: 129

• Message text: Class element ID '&1' does not exist in class '&2'

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /IWBEP/CM_MGW_RT129 - Class element ID '&1' does not exist in class '&2' ?

  The SAP error message /IWBEP/CM_MGW_RT129 Class element ID '&1' does not exist in class '&2' typically occurs in the context of SAP Gateway and OData services. This error indicates that the system is trying to access a class element (like a property or field) that is not defined in the specified class.
  Cause:
  
  Missing Class Element: The specified class element ID (&1) does not exist in the class (&2). This could be due to a typo, a misconfiguration, or an oversight during the development of the OData service.
  Model Changes: If the underlying data model has changed (e.g., fields were removed or renamed), but the OData service has not been updated accordingly, this error can occur.
  Service Registration Issues: The OData service might not be properly registered or activated, leading to inconsistencies in the metadata.
  Authorization Issues: Sometimes, authorization issues can prevent access to certain elements, leading to this error.
  
  Solution:
  
  Check Class Definition: Verify that the class element ID exists in the specified class. You can do this by checking the relevant ABAP class or structure in the SAP system.
  Update OData Service: If there have been changes to the underlying data model, ensure that the OData service is updated. This may involve regenerating the service or adjusting the service definition.
  Regenerate Metadata: If the service has been modified, regenerate the metadata for the OData service. This can be done in the SAP Gateway Service Builder (transaction code /IWBEP/SEGW).
  Check Service Activation: Ensure that the OData service is properly activated in the SAP Gateway. You can check this in the transaction /IWFND/MAINT_SERVICE.
  Debugging: If the issue persists, consider debugging the OData service to trace where the error is occurring. This can provide insights into why the class element is not being recognized.
  Authorization Check: Ensure that the user has the necessary authorizations to access the class and its elements.
  
  Related Information:
  
  Transaction Codes:
  
  /IWBEP/SEGW: Service Builder for OData services.
  /IWFND/MAINT_SERVICE: Maintenance of OData services.
  
  
  Documentation: Refer to SAP Help documentation for OData services and SAP Gateway for more detailed information on service development and troubleshooting.
  SAP Notes: Check for any relevant SAP Notes that might address known issues related to this error message.
  
  By following these steps, you should be able to identify and resolve the issue causing the error message /IWBEP/CM_MGW_RT129.