Message type: E = Error
Message class:  S_CUS_IMG_ACTIVITY - IMG Activity 
Message number: 012
Message text: The customizing object & (type &) is not used in IMG activities
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The SAP error message S_CUS_IMG_ACTIVITY012 indicates that a specific customizing object (like a configuration or a setting) is not being utilized in any of the Implementation Guide (IMG) activities. This can occur when you are trying to access or modify a customizing object that is not linked to any active IMG activity.
Cause: Unused Customizing Object: The customizing object you are trying to access is not associated with any IMG activity, meaning it has not been defined or linked to any configuration tasks. Incorrect Configuration Path: You may be navigating to the wrong path in the IMG or trying to access a customizing object that is not relevant to your current configuration. Transport Issues: If the customizing object was recently transported from another system, it may not have been properly linked to the IMG activities in the target system.
Solution: Check IMG Activities: Verify that the customizing object you are trying to access is indeed linked
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