I hate to tell you, but this didn't work. I followed your instructions to the letter, and I gave it time, I didn't rush anything. I have a HD indicator light which tells me when the PC is "doing something" and I waited until it had done what it had to do. When I selected MSFS it already had a tick box in optimisation. It said it was already optimised. I came out of MSFS like you said. I even restarted the machine. But when running the program again, it only lasted 1 minute.