How to Clean Install Windows 10 and 11: Complete Step-by-Step Guide

A clean install is the best way to get a fast and stable system. Unlike an upgrade, it removes all accumulated clutter and installs Windows from scratch.

When you need a clean install:

• System became very slow
• Virus or malware infection
• Replacing SSD or hard drive
• Windows won't boot
• Want to start fresh

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Preparation — Do This Before You Start

1. Back Up Your Data

A clean install erases everything on the system partition. Back up:

• Documents, photos, videos — to external drive or cloud
• Browser bookmarks — export or sync via account
• Passwords — password manager or write them down
• License keys of installed software

2. Save Your Windows Key

wmic path SoftwareLicensingService get OA3xOriginalProductKey

3. Export Installed Programs List

Get-ItemProperty HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\* |
  Select-Object DisplayName, DisplayVersion |
  Sort-Object DisplayName |
  Export-Csv "$env:USERPROFILE\Desktop\programs.csv" -Encoding UTF8

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Step 1 — Create Bootable USB

1. Download Rufus and Windows ISO from microsoft.com
2. Select USB, ISO, partition scheme: GPT (UEFI) or MBR (Legacy)
3. Click START → wait for READY

Win + R → msinfo32 → BIOS Mode: UEFI → GPT | Legacy → MBR

To bypass TPM 2.0/Secure Boot requirements on older hardware, use Rufus's Extended Windows 11 Installation option when creating the USB.

Optional — back up Wi-Fi passwords before wiping the drive:

netsh wlan export profile folder=C:\WiFiBackup key=clear

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Step 2 — Boot from USB

Press Boot Menu key at startup:

Manufacturer	Key
ASUS	F8 or Esc
Gigabyte	F12
MSI	F11
Dell	F12
HP	F9
Lenovo	F12

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Step 3 — Installation Wizard

1. Select language → "Install now"
2. Enter product key or click "I don't have a product key"
3. Select edition (Home or Pro)
4. Accept license → "Next"
5. Choose "Custom: Install Windows only" ← clean install

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Step 4 — Disk Partitioning

Full wipe (recommended): Delete all partitions → select unallocated space → "Next"

Keep data drive: Delete only system partitions (C: and small system partitions), leave D: intact.

Partition	Size	Purpose
Recovery	~500 MB	WinRE
EFI System	100 MB	UEFI bootloader
MSR	16 MB	Reserved
Primary	Rest	Windows (C:)

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Step 5 — Installation Process

Windows copies files and restarts 2–3 times. Don't turn off the PC. Takes 15–30 minutes.

💡 To create a local account without Microsoft: when asked about network, click "I don't have internet" → "Continue with limited setup"

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Step 6 — Post-Install Setup

# Check for missing drivers
Get-PnpDevice | Where-Object {$_.Status -eq 'Error'}

1. Activation — Settings → System → Activation → Troubleshoot
2. Drivers — Windows Update → Optional Updates → Driver Updates
3. Updates — Win + I → Windows Update → Check for updates
4. Restore Wi-Fi: netsh wlan add profile filename="C:\WiFiBackup\ProfileName.xml"
5. Restore programs from your saved list

Check activation status:

(Get-WmiObject SoftwareLicensingProduct -Filter "Name like 'Windows%'" |
  Where-Object {$_.PartialProductKey}).LicenseStatus

1 = Licensed.

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Common Issues

"This PC can't run Windows 11": enable TPM and Secure Boot in BIOS, or reburn the USB in Rufus with TPM/Secure Boot requirements removed.

Setup doesn't show any drives: SATA/NVMe drivers are missing from the installer — use Load driver on the partition screen with a second USB containing the driver.

Stuck at "Just a moment": wait up to 10 minutes. If it persists, it's usually a driver issue — restart and try again.

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Summary

Stage	Action	Time
Preparation	Backup, key, program list	30 min
USB drive	Rufus + Windows ISO	15 min
Installation	Partitioning, copying files	30 min
Setup	OOBE, activation, drivers	30 min