Windows 7 Installation Error: “Setup was unable to create a new system partition or locate an existing system partition.”
I bought myself a copy of Windows 7 Professional, exited to have the real thing after using the release candidate for months. I put in my DVD, clicked through the first couple steps of the installation process, set up my hard drive partitions, and then the error message popped up: “Setup was unable to create a new system partition or locate an existing system partition.” I tried redoing the partitions, restarting, et cetera, but I kept getting the error every time.
After Googling for the error, I found that quite a few other people have had the same problem. Fortunately the fix is extremely simple. Go to your BIOS settings and change the hard drive to which you are installing Windows 7 to be first in the hard drive boot order. Also temporarily change the hard drive to be the primary boot device (instead of a CD/DVD drive or a floppy drive). Restart, and when the computer first boots, you will probably need to press a key when it asks to boot from the DVD drive. Do so, and start the installation process again. You should then be able to go through the installation with no problems. Once Windows 7 is installed, you can return to the BIOS settings and change the boot device orders back to how you want them.
Many thanks to LinuxUser77 on Microsoft TechNet for providing the solution: http://social.technet.microsoft.com/Forums/en/w7itproinstall/thread/8c26780a-78ba-4113-994b-a0ef2c117c76.