Message type: E = Error
Message class:  RSTCO_ACT - Activation of technical content 
Message number: 012
Message text: &4: &1 ESSENTIAL objects selected for activation
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The SAP error message RSTCO_ACT012 typically occurs during the activation of objects in the SAP system, particularly when dealing with the transport of objects or during the activation of business content. The message indicates that there are essential objects that need to be activated, but the activation process has encountered an issue.
Cause: The error message RSTCO_ACT012 is generally caused by one of the following reasons: Missing Dependencies: The essential objects that are required for activation may have dependencies that are not met. This can happen if certain objects have not been transported or activated yet. Transport Issues: There may be issues with the transport request that contains the objects, such as incomplete transport or conflicts with existing objects. Authorization Issues: The user attempting to activate the objects may not have the necessary authorizations to perform the activation. System Configuration: There may be configuration issues in the system that prevent the activation of the objects.
Solution: To resolve
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