I just wanted to thank you for posting this workaround.
It worked brilliantly for me and increased my windows knowledge in the process.
I have been using FSX for some time now and I have so many additions I often wondered if a reinstall might be a good idea, but was a bit hesitant fearing any problems.
I then came across FSX-SE at a great price recently, which provided the possibility of having both on the one pc.
I have a nice clean FSX-SE now installed on a different drive and am enjoying installing the addons I really like and seeing their effects on performance.
Thanks again, Patrick