Step-By-Step: Completing a Clean Windows 8.1 Install With a Windows 8 Key

One question the CANITPRO team receives quite frequently, besides how to download the Windows 8.1 ISO, is how to perform a clean install of Windows 8.1 with a Windows 8 key.  Many IT professionals are looking for ways to save time migrating there organizations computers to Windows 8.1 now that the end of support for Windows XP is upon us.  We have detailed many ways of completing mass deployments of Windows 8.1 and while the steps can be completed by any size organization, we at CANITPRO wanted to also ensure we provided steps for small businesses as well. This post will detail ways to install Windows 8.1 utilizing your Windows 8 key better suited for small organizations.

NOTE: This method only works with Windows 8.1 Pro or Enterprise.

Step 1: Downloading Windows 8.1 Pro

  1. With Windows 8 license key in hand, select the button below to start the download for Windows 8 Pro. 

  2. Enter your Windows 8 key when prompted.


  3. Once the license key is entered, the WindowsSetupBox.exe will respond with the corresponding version of Windows 8 Pro to install. Click Next to continue
  4. When the download starts, wait until it hits 1% downloaded, then close the application thus cancelling the download.
  5. Select to the button below to start the download of Windows 8.1 Pro. 

    NOTE: Follow this link to download Windows 8.1 for Enterprise ISO. 

  6. When asked run the WindowsSetupBox.exe file


  7. The download of the corresponding Windows 8.1 version commences.

    No installation of Windows 8.1 begins at this time. Only the files required for the installation are downloaded.


  8. Once the download has completed, you are presented with the following choices:

    Install now: Will immediately install Windows 8 or 8.1 on the computer it is downloaded on

    Install by creating media: Will create an ISO of Windows 8 or 8.1 to installed via a bootable USB or DVD

    Install later from your desktop: Creates an executable to install Windows 8 or 8.1 later from your computer

    Select Install by creating media and then select Next

  9. Next you are provided the option to either create a bootable USB Flash Drive or create an ISO file to burn to a disk later.  In this scenario, it is suggested to utilize a 4 to 8GB USB stick inserted into your computer's USB port. Once inserted, select ISO USB Flash drive and direct the install to the newly ported USB stick.

    NOTE: The USB stick will be formatted thus all contents on the drive will be deleted

Step 2: Prepping Your Newly Created USB Key For a Clean Windows 8.1 Install


  1. Once the now bootable USB stick has been successfully created, navigate via file explorer to <drive letter>:\Windows81\sources on the newly created USB stick.
  2. Create a new text document by right-clicking in the folder, selecting New > Text Document
  3. Enter the following in the newly opened Notepad window:

  4. Save the newly created document in the <drive letter>:\Windows81\sources folder and name the newly created file as ei.cfg
    The installation key will now be required after install has been completed and will accept a windows 8 key

  5. Insert the USB into the computer you wish to install Windows 8.1 on and complete the necessary installation steps.
  6. After the installation is completed enter the Windows 8 key when requested.

That completes the Windows 8.1 clean installation. To add, the newly created bootable USB key can be used as many times as required by the installer. Be sure to also checkout, Microsoft Virtual Academy which provides a great resource in regards to furthering knowledge on Windows 8.1 for business.  Check out the latest module entitled:  Small Business: What’s New in Windows 8.1 for IT Professionals

Comments (2)

  1. DAS Certification Malaysia says:

    Thank you for your tips. Clean and clear!

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