Just be aware (I saw some comment from someone saying that their new machine would arrive tomorrow and they would be re-installing FSX) that you can ONLY USE THE PRODUCT KEY TO ACTIVATE THIS TWICE using the Product Key that came in the DVD case. Activation is requiree after an install.
After that, you get an error message stating that you have exceeded the activation count. You can get around this with a call to Microsoft (either an auth code for you existing Prod Key or they'll issue you a new product key) but be prepared for the usual long, drawn-out process.
I know that this is all in the aid of copy protection (which I support) but as it is based on your hardware, if you change your machine (upgrade etc), you'll be required to re-active. Logic would indicate that if you re-install this on the same machine where it was originally installed, that the hardware hash would match the original activation one and you wouldn't have a problem but.... as you might expect, I'm not gonna test this anytime soon 😀 😀
Just putting this out there in it's own, subject specific post, so others don't get caught like I did....
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