Just This

If you purchased an upgrade of Windows 7, you probably know that you need to have XP or Vista prior to upgrading to Windows 7. However, if you format your hard drive before installing Windows 7 with the upgrade disc, you may receive an error message when you enter your product key saying that it’s not valid. Since you need to have XP or Vista already installed, the product key is invalid if you no longer have the older version of Windows installed.

The obvious solution is to reinstall the older version of Windows first, and then run the Windows 7 upgrade again, but that can be a hassle. To save time, there is a work-around that lets you use the product key after all. Leave the product-key box blank and finish the installation process. Leave the upgrade disc in the drive, and once you are in Windows 7, go to the disc and run the installer again from within Windows. Follow the steps, and once it’s done “upgrading,” or installing for the second time, you can enter your product key with no problems.

This might be a flaw in the installation process, but it seems that “upgrading” an un-activated installation of the same Windows 7 version lets you use the product key from an upgrade license.

Important: Realize that using this solution to be able to use an upgrade disc without owning XP or Vista for the same computer already is a violation of the upgrade license. I am only providing this information for convenience if you are within the license terms and simply didn’t realize that you cannot format your hard drive first. Utilizing this work-around for any other purpose is illegal.

I found this solution at http://www.oit.umn.edu/utools/all-software/windows-7-upgrade/.

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.