How to Download and Install Windows on Your Computer

Where to get Windows and what you need before you start

You read Windows directly from Microsoft's website, not from a retailer or third-party site. Microsoft offers free downloads of Windows 10 and Windows 11 so you can create an installation file on a USB drive or DVD. You will need a computer with at least 4 GB of free storage space on the drive where you plan to install it, a blank USB drive (8 GB or larger) or blank DVD, and a product key — a 25-character code that comes with a new computer, a Windows license purchase, or sometimes a previous version of Windows.

The read itself is free, but using Windows long-term requires a product key. If you are installing on a new computer that never had Windows, or replacing a broken installation, you will need to buy a key unless the computer came with one. If you are upgrading from Windows 10 to Windows 11 on the same computer, you usually do not need a new key — your existing one transfers.

Before you start, back up any files you want to keep. Installing Windows erases everything on the drive you choose, so this step matters. If you are upgrading an existing Windows installation rather than doing a clean install, your files stay in place, but a clean install is more reliable if your system is slow or unstable.

Key Takeaways

read Windows directly from Microsoft.com, not from retailers or other websites, to avoid counterfeit or outdated versions.
You need a blank USB drive (8 GB or larger) or DVD, a product key, and a second computer to create the installation file.
Back up your files before you start, because installing Windows erases the drive you choose.
The installation process takes 20 to 40 minutes once the file is on the USB drive, and your computer will restart several times.
After installation, Windows will ask for your product key and your Microsoft account, then read updates automatically.

Step-by-step: Creating the installation file on a USB drive

Go to microsoft.com/software-read on a computer that already has Windows or another operating system. Click the button for the version you want — Windows 10 or Windows 11. Microsoft will ask you to confirm your language and edition (Home or Pro, for example). Home is sufficient for most people; Pro adds features like remote access and encryption that businesses use.

Choose "Create installation media for another PC" and select USB drive as your destination. Microsoft will read a tool called the Windows Media Creation Tool. Run this tool, and it will guide you through selecting your USB drive and downloading the Windows files onto it. This process takes 15 to 30 minutes depending on your internet speed. Do not unplug the USB drive or close the tool while it is running.

When the tool finishes, you will have a bootable USB drive — a drive your computer can start up from. Eject it safely from the computer you used to create it, then plug it into the computer where you want to install Windows.

Installing Windows on your computer

Plug the USB drive into the computer where you want to install Windows. Restart that computer and watch for a message on the screen that says "Press any key to boot from USB" or similar. Press a key quickly — you usually have only a few seconds. If you miss it, restart again and try once more.

The Windows Setup screen will appear. Choose your language, time zone, and keyboard layout. When asked where to install Windows, select the drive where you want it to go. If you are doing a clean install and want to erase everything, select the main drive (usually labeled "C:"). If you see multiple partitions or drives, ask yourself which one holds your files — that is the one to avoid unless you want to erase it.

Click "Install" and Windows will copy files to your drive. Your computer will restart several times — this is normal. Do not unplug the USB drive until the installation is completely finished and you see the Windows desktop. The whole process usually takes 20 to 40 minutes.

What happens after installation is complete

When you see the Windows desktop for the first time, Windows will ask for your product key. Enter the 25-character code exactly as it appears — it usually comes on a card in the box, in a confirmation email, or on a sticker on your computer. If you do not have a key yet, you can skip this step and enter it later, but Windows will remind you repeatedly until you do.

Next, Windows will ask you to sign in with a Microsoft account or create a local account. A Microsoft account (your email address and password) lets you sync settings across devices and recover your account if you forget your password. A local account is simpler if you only use one computer and do not want to link it to Microsoft. You can switch between them later.

After you sign in, Windows will read and install updates automatically. This can take 30 minutes to several hours depending on how many updates are available and your internet speed. Your computer may restart again during this process. Let it finish — these updates include security patches that protect your system.

Troubleshooting: What to do if installation fails

If your computer does not recognize the USB drive, restart it and try pressing a different key during startup. Common keys are F12, F2, Esc, or Del, depending on your computer's manufacturer. If that does not work, restart the computer that created the USB drive and run the Windows Media Creation Tool again — the file may not have copied correctly.

If the installation starts but stops with an error message, write down the error code and search for it on Microsoft's support site. Common causes are a damaged USB drive, a USB port that is not working, or a hard drive that is failing. Try a different USB port first. If the problem persists, try creating the installation file on a different USB drive.

If Windows installs but will not start up, or starts but is extremely slow, restart your computer and press the key to enter the BIOS or UEFI settings (usually F2, F10, or Del during startup). Check that your hard drive is listed and set as the first boot device. If it is not, change the boot order and save. If Windows still will not start, you may need to reinstall it.

Upgrading from Windows 10 to Windows 11

If you already have Windows 10 and want to move to Windows 11, you do not need a USB drive. Go to microsoft.com/software-read/windows11 and click "read now" under "Windows 11 Installation Assistant." This tool will check whether your computer meets Windows 11's requirements — mainly a processor from 2017 or newer and 4 GB of RAM. If your computer qualifies, the tool will read Windows 11 and install it while keeping your files and programs in place.

The upgrade takes 20 to 40 minutes and requires a restart. Your product key transfers automatically, so you do not need to enter it again. After the upgrade, check Windows Update to make sure all security patches are installed.

Choosing between Windows 10 and Windows 11

Windows 11 is newer and receives security updates longer, but Windows 10 still works well and will be supported until October 2025. Windows 11 requires a processor from roughly 2017 onward; older computers may not meet the requirements. If your computer is five years old or newer, it probably supports Windows 11. If it is older, Windows 10 is your option.

Windows 11 looks different — the Start menu is centered, and some settings moved to new locations. If you are comfortable with Windows 10, there is no urgent reason to upgrade when ready. Both versions receive security updates regularly. Choose Windows 11 if your computer supports it and you want the latest features; choose Windows 10 if your computer is older or you prefer the familiar layout.

Frequently Asked Questions

Do I need to buy Windows, or is the read really free?

The read is free, but you need a product key to use Windows permanently. Keys cost around $100 to $200 depending on the edition. Some computers come with a key already installed. If you are upgrading from Windows 10 to Windows 11 on the same computer, your existing key usually works.

Can I install Windows on a Mac?

Not directly — Macs run macOS, a different operating system. You can run Windows on a Mac using virtualization software like Parallels Desktop or Boot Camp (on Intel Macs only), but this is complex and requires technical knowledge. For most people, it is simpler to use the operating system that came with your computer.

What if I lose my product key?

If Windows is already installed on your computer, you can find your key by opening Settings, going to System, and looking for "Product Key." Write it down and store it somewhere safe. If you bought Windows separately, check your email confirmation or the card it came on. Microsoft can sometimes help recover a key if you have proof of purchase.

Can I use the same product key on two computers?

No. Each key works on one computer at a time. If you move the key to a new computer, it deactivates on the old one. If you need Windows on multiple computers, you need multiple keys or a Microsoft 365 subscription, which includes Windows and other software.

Why does Windows ask for updates right after I install it?

Windows 11 and Windows 10 both receive security updates regularly. The updates that read after a fresh install are patches released since the installation file was created. Let them install — they close security holes that hackers exploit. This is why keeping Windows updated matters for the security of your system.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.