By Adam Smart, Ecokeys Support Engineer — Last updated 11 August 2026

Before Installing Windows 11 from USB

Booting from Windows installation media is most commonly used when you want to:

• perform a clean Windows 11 installation;
• reinstall Windows on the same computer;
• install Windows after replacing the system drive;
• install Windows on a new compatible PC; or
• access Windows recovery and repair options.

1. Back up important files

Copy anything you cannot afford to lose to another device or trusted backup location.

This may include:

• documents and photographs;
• browser bookmarks;
• email archives;
• passwords and account information;
• software licence information;
• specialist application data; and
• drivers required for unusual storage or network hardware.

2. Check the current Windows edition and activation

If Windows is still running, open:

Settings > System > Activation

Record whether Windows is activated and whether the PC currently uses Windows 11 Home or Windows 11 Pro.

If you are reinstalling Windows on hardware that already has an appropriate digital licence, installing the same edition normally allows Windows to reactivate after the installation connects to the internet.

3. Confirm Windows 11 compatibility

Windows 11 requires compatible hardware including TPM 2.0, UEFI firmware with Secure Boot capability and a supported processor.

If there is any doubt, use our Windows 11 compatibility guide before beginning the installation.

4. Make sure the bootable USB is ready

You need Windows 11 installation media created from Microsoft's official Windows installation files.

If you do not already have it, follow our guide to creating a bootable Windows USB drive.

How to Boot the PC from the Windows 11 USB

1. Shut down the target PC.
2. Insert the Windows 11 USB.
3. Switch the computer on.
4. Immediately open the manufacturer's temporary boot menu.
5. Select the USB device, preferably its UEFI entry where more than one appears.
6. Wait for Windows Setup to load.

Common boot-menu keys include F12, F11, F9 and Esc, but the correct key varies between manufacturers.

If you are unsure, check the PC or motherboard manufacturer's instructions rather than repeatedly changing firmware settings.

The USB is ignored and Windows starts normally

This normally means the internal drive was selected before the USB.

Restart the computer and use the one-time boot menu again. There is usually no need to permanently change the entire boot order simply to install Windows once.

How to Install Windows 11 from USB

Step 1: Choose the language and keyboard

Select the appropriate language, regional settings and keyboard layout presented by Windows Setup, then continue.

Step 2: Start the Windows installation

Select the option to install Windows.

The exact wording and appearance of Windows Setup can change between Windows releases, so follow the current prompts displayed on screen.

Step 3: Enter the Windows product key when required

Windows Setup may ask for a product key.

If the PC already has a digital licence

If you are reinstalling the same Windows edition on the same activated hardware, you can normally select I don't have a product key where that option is provided.

Install the edition that was previously activated. Windows should attempt to reactivate automatically after installation once the computer is online.

If this is a new Windows licence

Enter the appropriate Windows product key when requested, or complete activation after Windows has been installed where Windows Setup permits this.

Step 4: Choose the Correct Windows 11 Edition

If Windows Setup asks you to select an edition, choose the edition that matches the licence or digital entitlement you intend to use.

Why is there no Home or Pro selection screen?

Some computers contain a Windows product key in their firmware. Windows Setup can detect that information and automatically select the corresponding edition.

For example, a PC originally supplied with Windows Home may automatically install Home without displaying an edition-selection screen.

If you genuinely need to move an activated Windows Home installation to Pro later, a valid Pro key can normally be entered through:

Settings > System > Activation > Change product key

For more detail about the editions, see our Windows 11 Home vs Pro comparison.

Step 5: Accept Microsoft's licence terms

Read the Microsoft Software Licence Terms displayed by Windows Setup.

If you agree to the terms, select the required acceptance option and continue.

Step 6: Choose the installation type

When performing a clean installation from bootable USB, select the option for installing a fresh copy of Windows rather than retaining the existing installation.

Step 7: Choose Where to Install Windows

This is the stage where the greatest care is required.

Windows Setup will display the drives and partitions it can see. Select the correct destination for the Windows installation.

Installing on a new empty SSD

A new drive may appear as Unallocated Space. Select the correct unallocated drive and allow Windows Setup to create the required system partitions.

Performing a completely clean reinstall

On a fully backed-up Windows system drive, experienced users may remove the existing Windows partitions and install to the resulting unallocated space.

Do not delete partitions on:

• secondary storage drives;
• external backup drives;
• manufacturer recovery partitions you intend to retain; or
• drives containing data you have not backed up.

Disconnect unnecessary drives where practical

If the PC contains several internal or external storage devices and you are uncertain which is which, disconnecting unnecessary drives before the clean installation can reduce the risk of selecting the wrong one.

Step 8: Allow Windows 11 to Install

Windows will copy the installation files, configure features and restart the computer several times.

Do not switch off the PC while Windows Setup is actively installing.

The installation starts again after the first restart

If the computer returns to the beginning of Windows Setup, it has probably booted from the USB again.

Allow the internal Windows drive to boot after the installation restart. Remove the USB when appropriate or use the boot menu to select the internal system drive.

Step 9: Complete Windows 11 Initial Setup

After installation, Windows will guide you through its initial setup screens.

This normally includes:

• confirming the country or region;
• choosing a keyboard layout;
• connecting to a network;
• signing in with the required Microsoft account;
• creating or confirming sign-in security;
• reviewing privacy choices; and
• allowing Windows to finish preparing the desktop.

Windows 11 Home and Windows 11 Pro for personal use require an internet connection and Microsoft account during Microsoft's normal initial setup process.

How to Activate Windows 11 After Installation

Once you reach the Windows desktop:

1. Connect the PC to the internet.
2. Open Settings > System > Activation.
3. Confirm the installed Windows edition.
4. Check the activation status.

If Windows activates automatically

No further activation action should be necessary.

This is common when the same Windows edition has been reinstalled on hardware that already holds an appropriate digital licence.

If you still need to enter a product key

Open:

Settings > System > Activation > Change product key

Enter the valid key for the edition installed.

For detailed activation steps, see our Windows 11 activation guide.

What to Do After Installing Windows 11

Do not consider the job finished as soon as the desktop appears.

1. Open Settings > Windows Update.
2. Select Check for updates.
3. Install available Windows and driver updates.
4. Restart the computer when required.
5. Check Windows Update again after restarting.
6. Open Device Manager and check for missing devices or warning symbols.
7. Install manufacturer drivers where Windows has not supplied suitable ones.
8. Confirm Windows activation.
9. Reinstall trusted applications.
10. Restore personal files from the backup.
11. Create a new recovery and backup plan.

Check manufacturer drivers

Windows Update installs many drivers automatically, but some systems require manufacturer-specific software for:

• chipset devices;
• graphics hardware;
• Wi-Fi and Bluetooth;
• audio;
• touchpads and hotkeys;
• storage controllers; and
• specialist laptop or motherboard functions.

Use the PC, motherboard or hardware manufacturer's official support site rather than random driver-download websites.

Windows 11 USB Installation Troubleshooting

The PC will not boot from the USB

Try these checks:

• Use the manufacturer's temporary boot menu.
• Choose the UEFI USB entry where appropriate.
• Try another USB port.
• Recreate the installation media.
• Try another USB flash drive.
• Check that the computer supports UEFI and the required Windows 11 security features.

The Windows installer cannot see the SSD

This can occur when Windows Setup does not have the required storage-controller driver.

It is particularly common on some computers using Intel VMD, RAID or manufacturer-specific storage configurations.

Check the manufacturer's support page for the appropriate storage driver. Windows Setup includes a Load driver option on the disk-selection screen where an additional storage driver is required.

"This PC can't run Windows 11"

If Windows Setup reports a compatibility problem, check:

• TPM 2.0;
• Secure Boot capability;
• UEFI boot mode;
• processor compatibility;
• memory;
• storage; and
• graphics requirements.

Use our Windows 11 compatibility guide rather than immediately trying to bypass Microsoft's checks.

Windows 11 Home installs instead of Pro

The PC may contain a Windows Home product key in its firmware, causing Setup to select Home automatically.

Allow Home to complete installation and activate where appropriate. If you have a valid Windows Pro licence and genuinely need Pro, use:

Settings > System > Activation > Change product key

to perform the edition upgrade.

The product key is not accepted

First confirm:

• the exact Windows edition installed;
• the exact edition the key is intended for; and
• the full activation error code.

Then use our Windows product key not working guide.

The installation keeps restarting from the beginning

The computer is probably booting from the USB after every restart.

Once Windows has copied the files and restarts, allow the internal system drive to boot rather than starting again from USB.

Windows Setup freezes or displays an error

Try:

• disconnecting unnecessary peripherals;
• recreating the Windows USB;
• using a different USB drive;
• using another USB port;
• checking the memory and SSD for hardware faults;
• installing current motherboard or PC firmware where appropriate; and
• recording the exact Windows Setup error before troubleshooting further.

Clean Installation vs In-Place Upgrade

Installing Windows 11 from USB: Final Checklist

• Important files have been backed up.
• The target PC is compatible with Windows 11.
• The bootable USB was created from official Microsoft files.
• You know whether Windows Home or Pro is required.
• You have recorded the existing activation status where possible.
• You know which physical drive Windows should be installed on.
• Unnecessary external storage has been disconnected where practical.
• You understand that deleting or formatting partitions can permanently erase data.

Taking a few minutes to verify those points is much safer than trying to correct the wrong edition, drive or partition after Windows Setup has already started.

Frequently Asked Questions