How To Fix SWN016 - No handler assigned to notification with key &1

SAP Error Message - Details

• Message type: E = Error

• Message class: SWN - WF Notif: Messages

• Message number: 016

• Message text: No handler assigned to notification with key &1

What causes this issue?

No handler class could be assigned when creating a notification for the
application object with the key value &V1&. No handler for notifications
has entered for the assigned category.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Enter a handler for notifications in the default category of the
scenario.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message SWN016 - No handler assigned to notification with key &1 ?

  The SAP error message SWN016 ("No handler assigned to notification with key &1") typically occurs in the context of the SAP Workflow Notification system, particularly when using the SAP Business Workflow or the SAP Business Workplace. This error indicates that there is no handler (or processing function) assigned to the notification that is being triggered.
  Cause:
  
  
  Missing Handler Assignment: The most common cause of this error is that the notification type does not have a corresponding handler assigned in the system. This can happen if the notification type is not properly configured or if the necessary function module or method is not defined.
  
  
  Incorrect Configuration: The configuration for the notification type may be incorrect or incomplete, leading to the system being unable to find the appropriate handler.
  
  
  Transport Issues: If the notification type was transported from one system to another (e.g., from development to production), the handler might not have been included in the transport request.
  
  
  Custom Development: If there are custom notifications or handlers, they may not be properly implemented or activated.
  
  
  Solution:
  
  
  Check Notification Type Configuration:
  
  Go to transaction code SWN1 (for Workflow Notifications).
  Check the configuration for the notification type that is causing the error.
  Ensure that a handler is assigned to the notification type.
  
  
  
  Assign a Handler:
  
  If no handler is assigned, you will need to assign a suitable handler. This can be done in the configuration settings for the notification type.
  You may need to create a new handler if one does not exist.
  
  
  
  Review Custom Code:
  
  If you are using custom notifications, review the custom code to ensure that the handler is correctly implemented and activated.
  
  
  
  Transport Check:
  
  If the issue arose after a transport, check the transport logs to ensure that all necessary objects were included in the transport request.
  
  
  
  Testing:
  
  After making changes, test the notification to ensure that it is now being processed correctly.
  
  
  
  Related Information:
  
  
  Transaction Codes:
  
  SWN1: Workflow Notification Configuration
  SWI1: Work Item Selection
  SWI2_DIAG: Work Item Diagnosis
  
  
  
  Documentation: Refer to SAP Help documentation for detailed information on configuring workflow notifications and handlers.
  
  
  SAP Notes: Check SAP Notes for any known issues or patches related to the SWN016 error message.
  
  
  Debugging: If the issue persists, consider debugging the workflow to trace where the notification is failing to find the handler.
  
  
  By following these steps, you should be able to resolve the SWN016 error and ensure that notifications are processed correctly in your SAP system.