How To Fix DNO021 - A notification with number &1 already exists

SAP Error Message - Details

• Message type: E = Error

• Message class: DNO - Messages for General Notifications

• Message number: 021

• Message text: A notification with number &1 already exists

What causes this issue?

There is already a notification in the System with the number &1.

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?

Change your entry.

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 DNO021 - A notification with number &1 already exists ?

  The SAP error message DNO021 indicates that a notification with the specified number already exists in the system. This typically occurs when you attempt to create a new notification using a number that is already assigned to an existing notification.
  Cause:
  
  Duplicate Notification Number: The most common cause is that the notification number you are trying to use is already in use by another notification.
  Manual Entry Error: Users may inadvertently enter a notification number that has already been created.
  System Configuration: The system may be configured to allow manual entry of notification numbers, leading to potential conflicts.
  
  Solution:
  
  
  Check Existing Notifications: Before creating a new notification, check the existing notifications to see if the number you are trying to use is already assigned. You can do this by using transaction codes like IW21 (Create Notification) or IW22 (Change Notification) and searching for the notification number.
  
  
  Use Automatic Number Assignment: If your organization allows it, consider using the automatic number assignment feature instead of manually entering a notification number. This can help prevent conflicts and ensure that each notification has a unique number.
  
  
  Change the Notification Number: If you need to create a new notification and the number is already in use, simply choose a different number that is not currently assigned.
  
  
  Review Configuration Settings: If this issue occurs frequently, review the configuration settings in the SAP system regarding notification number assignment. You may want to restrict manual entry or adjust the number range settings.
  
  
  Consult with SAP Support: If the problem persists or if you believe it is a system error, consider reaching out to SAP support for further assistance.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as IW21 (Create Notification), IW22 (Change Notification), and IW23 (Display Notification) to manage notifications effectively.
  User Authorization: Ensure that you have the necessary authorizations to create and manage notifications in the SAP system.
  Documentation: Refer to SAP documentation or help files for more detailed information on notification management and error handling.
  
  By following these steps, you should be able to resolve the DNO021 error and manage notifications more effectively in your SAP system.