Fix: ‘Setup was Unable to Use the Existing Partition’

By: Marian Cularea
3 minute read

I know that most of you at one point or another tried to rollback to a previous version of Windows and in this case we are going to talk a bit about rolling back from Windows 8.1 to Windows 8 operating system. You will find out by reading the lines below what you can do in order to fix your Windows 8 and get rid of the message “Setup was unable to use the existing partition because it does not contain the required free space”.
Fix Setup was unable to use the existing partition because it does not contain the required free space (Windows 8, Windows 8.1)
Usually the error message “Setup was unable to use the existing partition because it does not contain the required free space” appears when you have additional Hard Drivers connected to your device or the partition you are trying to install Windows 8 on is not completely blank.

Tutorial on how to fix message “Setup was unable to use the existing partition” in Windows 8:

First of all and most importantly you will need to create a backup copy of your current files, folders and any other important documents to prevent any future issues before attempting the steps below.

First Method:

  1. Unplug any USB sticks, USB external Drivers you might have connected to your device.
  2. Reboot your Windows 8.1 operating system with the devices above unplugged.
  3. Try running the setup process now and see if you still get the same message telling you that you do not have enough free space.

Second Method:

As explained above after you made the necessary backup copy of your important data you will need to completely format the partition you wish to install your Windows 8 on.

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  1. Turn on the Windows 8.1 device.
  2. After the device started insert your Windows 8 Installation Media into the CD or DVD ROM.
  3. Reboot your Windows device with the Installation media inserted.
  4. It will ask you while the device starts to press any key to boot from the CD or DVD.
  5. Press any key on the keyboard to boot from the CD or DVD.
  6. In the first window that appears from the installation media you will need to select your language.
  7. After you are done left click or tap on the “next” button.
  8. Left click or tap on the “Install Windows” button.
  9. In the window “Enter the product key to activate Windows” you will need to write the Windows 8 product key.
  10. The next page will be “Please read the license terms” and you will need to left click or tap on the “I accept the license terms” and then left click or tap on the “Next” button.
  11. On the next page it will ask you which type of installation do you want.
  12. Left click or tap on the “Custom” button.
  13. Next window will be “Where do you want to install Windows?” and there you will need to left click or tap on the “Drive options (advanced)” feature.
  14. Left click the partition you want to install Windows 8 on.
  15. Left click or tap on the “Format” feature and continue with the instructions on the screen.
  16. After you are done left click or tap on the “Next” button.
  17. Now follow the instructions on the screen and finish your Windows 8 installation process.
  18. After Windows 8 has finished you will need to reboot your device once more and you are done.

That’s it, you now have a fix to the message “Setup was unable to use the existing partition because it does not contain the required free space” in your Windows operating system but if you need additional help you can write us in the comments section of the page situated below and I will help you further as soon as possible.

READ ALSO: Fix: Unable to Login with a Microsoft Account After Rollback from Windows 10

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