Message type: E = Error
Message class:  ILM_STOR_MON - [OBSOLETE] ILM Store: Monitoring Framework Messages 
Message number: 120
Message text: KPI '&1' already exists in register
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The SAP error message ILM_STOR_MON120 indicates that there is an attempt to register a Key Performance Indicator (KPI) that already exists in the system. This error typically arises in the context of Information Lifecycle Management (ILM) when dealing with storage monitoring.
Cause: The primary cause of this error is that the KPI you are trying to create or register is already present in the system. This can happen if: The KPI was previously registered and not properly deleted. There is a duplicate entry in the system due to a configuration error or a manual entry mistake.
Solution: To resolve this error, you can take the following steps: Check Existing KPIs: Navigate to the relevant transaction or report where KPIs are managed (e.g., ILM storage monitoring). Look for the KPI with the name or identifier specified in the error message (&1). Verify if it is indeed present in the system. Delete or Modify Existing KPI: If the KPI is no longer needed, you
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