How to install the Microsoft Windows operating system

Updated: 12/30/2021 by Computer Hope
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Each version of Microsoft Windows is installed on a computer using similar steps. While there are steps in the installation process that differ between versions of Windows, the following general steps and guidelines help you install Windows on your computer.


If you're replacing the hard drive in your computer, you must reinstall Windows again.

If you're replacing the motherboard in your computer, you may need to purchase a new licensed copy of Windows and install it. Microsoft has designed current versions of Windows to be tied to the motherboard in the computer when Windows is installed. So if you change the motherboard, the existing license, or product key, may no longer be valid.


To upgrade to a newer version of Windows on your computer, the steps on this page help you with the upgrade process. The Windows installation process should recognize if you have an older version of Windows already installed on the computer and ask to upgrade or perform a fresh install. The upgrade process installs the newer Windows operating system files over the old ones and preserve your files.

The steps below are for all recent versions of Windows, including Windows 98, Windows Me, Windows 2000, Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, and Windows 11. These steps even work for earlier versions (e.g., Windows 95) as long as you use the disc version. The floppy diskette version is similar, but it requires additional steps.


The install guidelines for Windows for a server have additional steps based on the type of server and version of Windows.

Check hardware compatibility

Before installing or upgrading Windows on your computer, check the hardware in the computer to make sure it's compatible with that version of Windows. Microsoft provides a Windows Compatible Products List for checking if the hardware in your computer is compatible with the chosen version of Windows.

If one or more pieces of hardware is not compatible with the chosen Windows version, we recommend replacing that hardware with compatible hardware or purchasing a new computer. Having compatible hardware in your computer helps ensure the Windows install or upgrade process is successful.

Genuine Windows CD, DVD, or USB thumb drive

First, you need a genuine copy of the Microsoft Windows operating system installation CD (compact disc), DVD (digital versatile disc), or USB thumb drive. A genuine Windows product key is included with the installation disc, which is required to activate Windows after installation. If you have an OEM (original equipment manufacturer) computer, the Windows product key is often on the back or side of the computer.

If you have an OEM computer (e.g., Acer, Dell, HP (Hewlett-Packard), etc.), the computer will not have a genuine Windows CD, DVD, or USB thumb drive. Instead, you would reinstall Windows and the software using a hidden partition or a set of restore discs. The steps mentioned on this page would still work, but you'd need a copy of Windows. You can borrow a friend's Windows disc, as long as it's the same version of Windows that came with the computer and have a product key.


With early versions of Windows, you cannot download a copy of Windows to install on a computer. You must purchase a physical copy of Windows. If you are installing Windows 10, you can download the Windows 10 Media Creation Tool to create a bootable disc or USB thumb drive. For Windows 11, you can download the Windows 11 Installation Assistant.


Microsoft has Windows 10 and 11 available for download only from their website. Any other site that claims to have copies of other versions of Windows should not be trusted. These copies of Windows are pirated software and could contain anything, including spyware or malware.

Installing or upgrading Windows

To start the Windows install or upgrade process, you must configure your computer to boot from a CD or DVD before booting to the hard drive. Changing the boot process forces the computer to look for the Windows installation disc before booting from the hard drive.

  1. Open the CMOS setup.
  1. Change the computer's boot order. Set the CD, DVD, or disc drive as the first boot device if you are trying to boot from a disc. Or, set the first boot device to your USB drive if you're trying to boot from a USB thumb drive. If the drive is not shown, keep the disc is inserted and reboot the computer. With the disc in the drive, BIOS (basic input/output system) should recognize and include it in the list.
  2. Save the settings change and exit BIOS.

Once you have updated the boot order, you can begin the Windows installation process.

  1. Place the Windows disc in the CD/DVD drive or USB thumb drive into the back of the computer.
  2. Turn on or restart the computer. As the computer starts up, it should detect the installation disc or drive and show a message similar to Press any key to boot from CD. Press any key on the keyboard to have the computer boot from the Windows disc or drive.
  3. After the Windows install begins, there are several prompts you must answer. Select either Yes or the appropriate option to install Windows.
Install Note

Make sure you select the Full Install option and not the Repair or Upgrade option.

Upgrade Note

If you are upgrading to a newer version of Windows, select the Upgrade option instead of the Full Install option.

  1. When asked which partition to install Windows onto, select the main partition, usually the C: drive or one labeled "Unallocated partition". If upgrading Windows, select the existing installation of Windows on the hard drive.
  2. You may be asked to erase all contents on the hard drive, then install Windows. We recommend you choose this option, as it also formats the hard drive to allow the Windows operating system to be installed.

You can use the erase all contents option to uninstall an existing version of Windows on the hard drive, then install Windows again.

  1. The computer may need to restart several times during the Windows install process. The restarts are normal and if prompted to restart, select the Yes option.
  2. When the install process is nearly complete, the Windows configuration option screens are shown. On these screens, you may be asked to select the time zone you live in, your preferred language, and the account's name you use to access Windows. Select the appropriate options and enter the appropriate information on each configuration screen.

The Windows install process is completed when the computer prompts you to log in or when it loads into Windows.

Final Windows and computer configuration

After Windows is installed on the computer, you must install the drivers and related software for the hardware in the computer. You can use the installation discs that came with the hardware or download the drivers from the hardware manufacturer's website.


If you cannot download drivers because your network card is not working after installing Windows, you can download the drivers on another computer. Then, copy them to a USB thumb drive, and move them over to your computer.

We strongly recommend you install the latest drivers for each piece of hardware.

To determine which hardware needs drivers to be installed, check the Device Manager and look for the exclamation mark "!" next to hardware devices. The exclamation point means drivers are needed for that device.

After installing the necessary hardware device drivers, install any programs on the computer that you want to use.

Finally, download and install any available Windows updates. Updating Windows improves the operating system's performance, the hardware in the computer, and the programs you use. It can also improve security by fixing potential security holes and flaws in Windows.

Long-term maintenance of Windows

Microsoft frequently releases new updates for Windows, so we recommend you check for and install available updates. Doing so helps keep Windows running better and keep your computer protected.

Also, periodically check for updated hardware device drivers from manufacturers' websites. Keeping hardware drivers updated helps the hardware devices in the computer run at peak performance and improves compatibility with other computer hardware and software.