Message type: E = Error
Message class:  SWN - WF Notif: Messages 
Message number: 137
Message text: Specify the required reliability
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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The SAP error message SWN137, which states "Specify the required reliability," typically occurs in the context of the SAP Workflow Notification (SWN) configuration. This error indicates that the system requires you to specify the reliability level for the notifications being sent out.
Cause: The error arises when the configuration for sending notifications via the SAP Workflow Notification (SWN) is incomplete or incorrect. Specifically, it means that the reliability parameter, which determines how the notifications are sent (e.g., whether they should be sent reliably or not), has not been set.
Solution: To resolve the SWN137 error, you need to specify the required reliability in the configuration settings. Here are the steps to do this: Access the SWN Configuration: Go to transaction code SWN1 in the SAP GUI. This will take you to the Workflow Notification configuration screen. Check the Notification Settings: In the configuration screen, look for the section where you can define the notification settings. This may include
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