Message type: E = Error
Message class:  S_ILM_VIEW_UI - Messages for View Configuration in Retention Warehouse 
Message number: 021
Message text: View &1 already exists
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The SAP error message S_ILM_VIEW_UI021 indicates that there is an attempt to create a view that already exists in the system. This error typically occurs in the context of Information Lifecycle Management (ILM) when you are trying to create a new view in the ILM framework, but a view with the same name or identifier already exists.
Cause: Duplicate View Creation: The most common cause is that a view with the same name has already been created in the system. System
Configuration Issues: There may be issues with the system configuration or inconsistencies in the database that lead to this error. Development or Transport Issues: If you are working in a development environment and have transported objects, there may be conflicts with existing views.
Solution: Check Existing Views: Use transaction codes like ILM_VIEW or SE11 to check if the view already exists. If it does, you may need to modify or delete the existing view instead
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