....are attempting this reinstall. Removed Linux and installing Windows, or trying to install windows with the Linux on there, and is GRUB running still as the bootloader, or the one that comes with Windows?
I have Linux on my laptop, I decided I wanted to go back to dual boot with Win7 for Flight Simulator. I am the original, new buyer of the OS' a brand new MS version that has only, ever been installed on this machine. Now when I go to reinstall in it gives me an "unauthentic authorization code" error.

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