How to Install Windows 11 Without USB Drive (Clean Install Method)

To do a clean install of Windows 11 without a USB drive, shrink your existing partition in Disk Management to create a 10 GB “Windows Installer Media” partition, copy the contents of a mounted Windows 11 ISO into it, reboot into the Windows Recovery Environment, open Command Prompt, and run setup.exe from that partition. This works on both supported and unsupported hardware (use setup.exe /product server to bypass Windows 11 hardware checks), and needs nothing beyond built-in Windows tools.

Applies to: Windows 10 (22H2) and Windows 11 (23H2, 24H2, 25H2) | Last updated: April 15, 2026

Key Takeaways

• A clean Windows 11 install works without a USB drive by shrinking your existing drive, creating a 10 GB partition, and copying the ISO contents onto it — Windows Setup can run from an internal partition just as well as external media.
• Boot into Windows Recovery Environment (WinRE) with Shift + Restart or Settings → System → Recovery → Advanced startup, open Command Prompt, and run setup.exe from the installation media partition.
• To install on unsupported hardware, run setup.exe /product server instead — this tells Windows Setup to skip the TPM, Secure Boot, and CPU compatibility checks.
• After install, the installation media partition takes up around 10 GB permanently. A Windows recovery partition is created between your C: drive and the installer partition, so the space can’t be reclaimed without resizing tools.
• If you need a local account without a Microsoft account, use the BypassNRO registry trick at OOBE, or follow my Windows 11 local account bypass guide for the latest working methods.

In This Guide

This guide walks through the full clean install process end-to-end. If you already have part of it done, jump to the relevant section:

• Step 1: Create a 10 GB installer partition — use Disk Management to shrink and format.
• Step 2: Download and copy the Windows 11 ISO — mount the ISO and copy all files to the partition.
• Step 3: Boot into Windows Recovery and open Command Prompt — Shift + Restart into WinRE.
• Step 4: Run setup.exe (with bypass if needed) — start the installer from the partition.
• Step 5: Partition the drive and install Windows — delete old partitions and let Setup rebuild.
• Step 6: Set up a local account and finish OOBE — skip the Microsoft account step.

When This Method Is the Right Choice

I’ve used this method in the shop more times than I can count — it’s the fix when a customer shows up with a laptop whose USB ports are all dead, or a machine where the BIOS can’t see any attached USB boot device. It also saves a trip to buy a flash drive when you’ve decided to reinstall Windows on the spot. The only real drawback is that you lose around 10 GB of drive space permanently, because the recovery partition that Windows creates between your C: drive and the installer partition blocks you from expanding C: back into that space.

If you can grab a USB stick, a Rufus install is still the cleanest route — see my Rufus bootable USB guide. But if you can’t, this method works reliably on both Windows 10 and Windows 11 systems.

Step 1: Create a 10 GB Installer Partition

You need a dedicated partition for the Windows installation files — not a folder on your existing C: drive. The installer doesn’t play nicely with being run from a live Windows install, and a separate partition also ensures the files survive when you wipe C: later.

1. Right-click the Start button and choose Disk Management.
2. Right-click your C: drive partition and choose Shrink Volume.
3. In Enter the amount of space to shrink in MB, type 10000 (10 GB). Click Shrink.
4. You’ll see a new block of unallocated space at the end of the drive.
5. Right-click the unallocated space and choose New Simple Volume.
6. Click through the wizard with defaults. On the format screen, set Volume label to Windows Installer Media.
7. Click Finish.

Note: Label the partition something unmistakable — the drive letters inside Windows Recovery Environment are reassigned and usually don’t match what you see now, so the label is how you’ll find it later.

Step 2: Download and Copy the Windows 11 ISO

Download the Windows 11 ISO from Microsoft directly — see my detailed guide on how to download the Windows 11 ISO if you need a walkthrough. If you specifically need an older build (23H2 or earlier), grab it from my guide on downloading old Windows ISOs. For Windows 10, use my Windows 10 ISO guide instead.

1. Open File Explorer and navigate to the downloaded ISO (usually in Downloads).
2. Right-click the ISO and choose Mount. A new File Explorer window opens with the ISO contents.
3. Select all files (Ctrl + A) and copy (Ctrl + C).
4. Open This PC, then open the Windows Installer Media partition.
5. Paste (Ctrl + V). Wait for the copy to finish — the total is around 5 GB.
6. Go back to This PC, right-click the mounted ISO drive (it’ll have a DVD icon), and choose Eject.

Pro tip: If you want a fully automated install (skip OOBE, preinstalled apps, debloat), drop an autounattend.xml answer file in the root of the partition alongside setup.exe. Windows Setup will pick it up automatically. The easiest way to get a good one is UnattendedWinstall.

Step 3: Boot into Windows Recovery and Open Command Prompt

You can’t run setup.exe against your current Windows drive from within that running Windows install. You need Windows Recovery Environment (WinRE), which boots a minimal Windows installation off your drive’s recovery partition.

Two Ways Into WinRE

• Shift + Restart: Hold Shift, click Start → Power → Restart. Keep Shift held until the blue recovery screen appears.
• Settings path: Settings → System → Recovery → Restart now under Advanced startup, then confirm with a second Restart now.

Navigate to Command Prompt

1. On the blue screen, click Troubleshoot.
2. Click Advanced options.
3. Click Command Prompt.
4. If prompted, select your user account and enter your Windows sign-in password.

Step 4: Run setup.exe From the Installer Partition

Drive letters inside WinRE are not the same as what you see in Windows. Your C: drive might be D:, and the Installer Media partition might be any letter. The easiest way to find which letter is which is to open Notepad.

Find the Installer Drive Letter

1. In Command Prompt, type notepad and press Enter.
2. In Notepad, click File → Open.
3. Click This PC in the left pane to see every available drive letter with its volume label.
4. Note the letter next to Windows Installer Media — let’s call it E: for this example.
5. Close Notepad.

Launch Windows Setup

Back in Command Prompt:

E:
dir
setup.exe

The dir output should list folders called boot, sources, efi, and a setup.exe file. If you see those, you’re on the right drive. Running setup.exe launches the full Windows 11 Setup wizard — the same one you’d see if you’d booted from a USB stick.

Bypass Hardware Requirements (If Needed)

If Setup tells you your PC doesn’t meet Windows 11 requirements, close the wizard and run this instead:

setup.exe /product server

The /product server switch makes Setup think it’s installing Windows Server, which doesn’t enforce the TPM 2.0, Secure Boot, or CPU family checks. The resulting install is still regular Windows 11 — the bypass only affects pre-install compatibility. For a deeper dive on unsupported hardware, see my Windows 11 unsupported hardware guide with FlyOOBE.

Note: Microsoft doesn’t officially support Windows 11 on unsupported hardware, and they’ve warned they can stop delivering updates at any time. In practice, every monthly cumulative update has continued to install on unsupported systems up to 24H2. Keep a backup plan, but don’t panic about updates stopping.

Step 5: Partition the Drive and Install Windows

Walk through the Setup wizard as normal until you reach the Where do you want to install Windows? screen. This is the critical step — you need to clear the old C: drive partitions while leaving the Windows Installer Media partition alone.

Warning: Deleting a partition wipes all data on it permanently. Make sure anything you want to keep has been backed up to an external drive, cloud storage, or a separate internal drive that you will not be touching here.

1. Identify the Windows Installer Media partition by its 10 GB size — do not delete this one.
2. Select each of the other partitions on the drive (the current C: partition, EFI, and Recovery) and click Delete. Confirm each prompt.
3. You’ll end up with one large block of unallocated space plus the 10 GB Installer Media partition.
4. Click the unallocated space and click Next. Windows Setup automatically creates the EFI, MSR, and primary partitions it needs.

Setup copies files, expands them, and reboots the PC several times. Total install time is usually 20–40 minutes on an SSD. When it’s done, you land at Windows 11’s out-of-box experience (OOBE).

Step 6: Finish OOBE With a Local Account

Windows 11 Home and Pro both push you toward signing in with a Microsoft account during OOBE. If you want a local account, use the BypassNRO registry key.

Disconnect from the Internet First

• Desktop: unplug the Ethernet cable.
• Laptop: press the Wi-Fi function key to turn wireless off, or don’t enter Wi-Fi credentials when asked.

Run the BypassNRO Trick

1. On the region selection screen, press Shift + F10 to open Command Prompt.
2. Run this one-liner to add the registry value and reboot OOBE:

reg add "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\OOBE" /v BypassNRO /t REG_DWORD /d 1 /f
shutdown /r /t 0

The system reboots, OOBE starts again, and this time the Continue with limited setup (local account) option appears when you reach the connect-to-internet screen. Click I don’t have internet, then Continue with limited setup.

If BypassNRO has been patched on your build (Microsoft removed it in preview builds 26220.6772+), try the ms-cxh:localonly dialog instead, or see my full Windows 11 local account bypass guide for the current working methods.

Complete the Setup

1. Enter a username for your local account.
2. Set a password (or leave blank — you can add one later in Settings).
3. Turn off every privacy toggle you don’t need (location, diagnostic data, tailored experiences, advertising ID).
4. Wait for the desktop to finish loading.

After the Install: Cleanup and Optimisation

• Reconnect to the internet — plug in the Ethernet cable or turn Wi-Fi back on and connect to your network.
• Check for updates — Settings → Windows Update → Check for updates. Install everything.
• Install drivers — see my guide on installing missing drivers with Snappy Driver Installer Origin.
• Debloat and optimise — run Winhance to remove the default Microsoft apps you don’t use and apply sensible privacy and performance defaults in one click.
• Restore files — copy your backup back from the external drive.

The 10 GB Partition Trade-Off

After install, open Disk Management and you’ll see the Windows Installer Media partition still sits at the end of the drive. Between C: and it, Windows Setup has placed a new ~650 MB recovery partition. That recovery partition blocks you from right-clicking C: and choosing Extend Volume — Extend only works into contiguous free space.

You have two practical options:

• Keep the Installer Media partition. It’s useful — you can run a repair install from it without hunting for a USB stick. 10 GB is cheap storage.
• Reclaim the space with a third-party partition tool (AOMEI Partition Assistant, MiniTool Partition Wizard, or DiskGenius). These can move the recovery partition and extend C: into the freed space. This is the only way to merge the space back without reinstalling.

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Frequently Asked Questions

Does this method work for Windows 10?

Yes, the process is identical. Download a Windows 10 ISO using my Windows 10 ISO guide instead of the Windows 11 one. You can also skip the /product server bypass — Windows 10 has no TPM or CPU compatibility checks, so vanilla setup.exe works on any hardware.

Is it safe to install Windows 11 on unsupported hardware?

For daily use, yes — unsupported installs have been working reliably since Windows 11 launched. Microsoft’s warning is that updates could theoretically stop, but in practice every cumulative update through 24H2 has installed correctly. The main risk is feature updates (e.g., jumping from 24H2 to a future release), which occasionally stall on older CPUs; in that case, you do another clean install with the bypass.

Can I delete the installation media partition after Windows is installed?

You can delete it with Disk Management, but the space won’t merge back into C: because Windows placed a recovery partition between them. To actually reclaim the space, use a partition tool like AOMEI Partition Assistant that can move the recovery partition aside and extend C: through the gap. Otherwise, leave the 10 GB partition — it’s useful for repair installs.

Why does my Start menu still have bloatware after a clean install?

Windows 11’s default Start menu includes pinned Microsoft apps and sponsored suggestions. A clean install doesn’t remove these by default. Run Winhance after OOBE to debloat the Start menu, remove unwanted apps, and disable sponsored content. For a fully debloated install from the start, use UnattendedWinstall dropped into the installer partition root.

Can I use this if I only have one partition on my drive?

Yes — the first step of this guide is shrinking your existing partition to create a new 10 GB one. As long as your drive has at least 10 GB of free space available to shrink into, the method works. Disk Management can shrink any NTFS volume that has contiguous free space.

What if Shift + F10 doesn’t open Command Prompt during OOBE?

Some OEMs disable the Shift + F10 shortcut on specific models (rare, but it happens on a few laptops). If it doesn’t work, unplug Ethernet and don’t connect to Wi-Fi at the “Let’s connect you to a network” screen — on current Windows 11 builds, the local account option appears automatically when there’s no network connection. If that also fails, my full Microsoft account bypass guide has every current working method.