A processor executive (PE) handles an operating system executive (OSE) in a secure environment. The secure environment has a platform key (PK) and is associated with an isolated memory area in the platform. The OSE manages a subset of an operating system (OS) running on the platform. The platform has a processor operating in one of a normal execution mode and an isolated execution mode. The isolated memory area is accessible to the processor in the isolated execution mode. A PE supplement supplements the PE with a PE manifest representing the PE and a PE identifier to identify the PE. A PE handler handles the PE using the PK and the PE supplement.