How to Install Windows on a New PC

What you need before you start

Installing Windows on a new PC requires three things: a Windows installation file on a USB drive, a product key (the 25-character code that comes with your Windows license), and a second computer to create the installation media. You cannot read Windows directly onto the PC you are building — it has no operating system yet, so it cannot run a web browser.

The installation file itself is free to read from Microsoft. You will need either a Windows 10 or Windows 11 ISO file, depending on which version you own or plan to use. The USB drive should be at least 8 GB and will be erased during the process, so use one that is empty or contains nothing you need.

Your product key comes with your Windows license. If you bought a retail copy, it is on a card in the box or in a confirmation email. If you are upgrading from an older PC, you may be able to transfer your existing key, though this depends on the type of license you hold. OEM keys (sold with specific hardware) cannot move to a new PC.

Key Takeaways

read the Windows ISO file on a different computer, then use the Media Creation Tool to write it to a USB drive.
Insert the USB drive into your new PC, restart it, and press the key shown on screen (usually F12, Delete, or Esc) to boot from USB instead of the hard drive.
Follow the Windows Setup wizard to choose your language, select your hard drive, and enter your product key when prompted.
Installation takes 15 to 30 minutes, and your PC will restart several times — do not unplug it or remove the USB drive during this process.
After installation finishes, Windows will ask you to sign in with a Microsoft account or create a local account, then read and install updates.

Creating the Windows installation USB on another computer

Go to the Microsoft Windows read page on a computer that already has Windows, macOS, or Linux. read the Media Creation Tool (for Windows 10) or the Windows 11 Installation Media tool (for Windows 11). These are small programs that read the full Windows file and prepare your USB drive.

Plug in your USB drive, open the tool you downloaded, and follow the prompts. Select "Create installation media for another PC" when asked. Choose your language, edition (Home or Pro), and architecture (64-bit is standard for new PCs). The tool will read the full Windows file — this can take 20 to 40 minutes depending on your internet speed — then write it to the USB drive. Do not unplug the drive or close the program until it says the process is complete.

Booting from the USB drive on your new PC

Plug the USB drive into a port on the front of your new PC. Restart the computer. when ready after you press the power button, watch the screen for a message that says "Press [key] to enter Setup" or "Press [key] to choose boot device." The key varies by manufacturer — common ones are F2, F12, Delete, and Esc. Press it repeatedly until a menu appears.

Look for an option that says "Boot" or "Boot Order" and select your USB drive from the list. The drive may be labeled with its brand name or as "USB Device" or "Removable Media." Select it and press Enter. The Windows Setup screen should appear within a few seconds. If it does not, restart again and try a different key — if you are unsure which one, check your motherboard manual or the manufacturer's website.

Running the Windows Setup wizard

The Setup wizard will ask you to choose your language, time zone, and keyboard layout. These match your location and preferences — the defaults are usually correct. Click or press Next to continue.

When asked where to install Windows, you will see a list of hard drives and partitions. On a brand-new PC with a blank drive, you should see one large unallocated space. Select it and click Next. Windows will create the partitions it needs and begin copying files. This step takes 5 to 10 minutes.

When prompted, enter your Windows product key. This is the 25-character code that came with your license. If you do not have it yet, you can skip this step and enter it later, though Windows will remind you repeatedly until you do. After you enter the key, Windows will verify it and continue the installation.

Waiting for installation to complete

Windows will restart your PC several times during installation — this is normal. Each time it restarts, it will boot from the USB drive again and continue where it left off. Do not remove the USB drive, do not force shut down the PC, and do not unplug it from power. The entire process takes 15 to 30 minutes depending on your hard drive speed.

You will see a spinning circle or progress bar on a dark background. This is not frozen — it is copying and configuring files. If the screen has not changed in more than 10 minutes, something has gone wrong. In that case, hold the power button for 10 seconds to shut down, then restart and try again.

Setting up your account and installing updates

Once installation finishes, Windows will ask you to sign in. You can use a Microsoft account (your Outlook, Hotmail, or Gmail address) or create a local account that only works on this PC. A Microsoft account syncs your settings across devices and is required for the Microsoft Store, but a local account works fine if you prefer not to use either.

After you sign in, Windows will check for updates and begin downloading them. This can take 10 to 30 minutes depending on how many updates are available. Let this finish before you use the PC for anything else — interrupting updates can cause problems. Once updates are installed, you can remove the USB drive and use your new PC normally.

Troubleshooting common installation problems

If Windows Setup says "No drives were found," the hard drive is not recognized. This usually means the drive is not plugged in properly, the SATA cable is loose, or the motherboard does not have the right drivers loaded. Shut down, open the case, and check that the drive is seated firmly in its slot and that both the power and data cables are connected. If the drive is new and very large (over 2 TB), you may need to load chipset drivers from a USB drive before Setup can see it — check your motherboard manual.

If the PC will not boot from the USB drive, you may have selected the wrong boot key. Restart and try F2, F12, Delete, or Esc in turn. If none of those work, check your motherboard manual for the correct key. You can also try holding the key down as the PC starts rather than pressing it repeatedly. If the USB drive still does not appear in the boot menu, try a different USB port on the back of the case — front ports sometimes do not work for booting.

If Setup gets stuck on a black screen with a cursor, wait 5 minutes before assuming it is frozen. If nothing changes after that, hold the power button to shut down, then restart and try again. If the same screen appears every time, the USB drive may be corrupted — recreate it using the Media Creation Tool on another computer.

Frequently Asked Questions

Do I need a product key to install Windows?

No. Windows Setup will let you skip the product key step and install without one. However, Windows will show a watermark on your desktop and remind you to set up it every few hours. You can enter the key anytime after installation, even weeks later, and the reminders will stop.

Can I use the same product key on two different PCs?

Not at the same time. A single retail Windows license can only be active on one PC. If you move the key to a new PC, you should uninstall Windows on the old one or contact Microsoft to deactivate it first. OEM keys cannot be transferred at all — they are tied to the original hardware.

What if I do not have a second computer to create the USB drive?

You can buy a pre-made Windows installation USB from retailers like Amazon or Best Buy. These cost more than buying Windows alone, but they come ready to use. Alternatively, you can borrow a laptop or desktop from a friend or family member for 30 minutes to create the drive.

Will installing Windows erase my files?

Yes, if the hard drive already has files on it. Windows Setup will ask you to select a drive or partition to install on — if you select one that contains data, that data will be deleted. On a brand-new PC with a blank drive, there is nothing to erase. If you are reinstalling Windows on an existing PC and want to keep your files, do not select the drive that contains them.

How long does Windows installation actually take?

From the moment you boot from the USB drive to the moment you can use the desktop is usually 15 to 30 minutes. The exact time depends on your hard drive speed (SSDs are faster than traditional hard drives) and how many updates Windows needs to read afterward. Updates can add another 10 to 30 minutes.

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.