Reinstalling Windows 10: create a USB stick, install, activate

If Windows 10 has become slow, errors are piling up or you want to pass a PC on, often only one thing helps: reinstalling Windows 10. This guide shows when a reset is enough, how to create a bootable USB stick, perform a clean installation of Windows and then activate it.

Key points at a glance

• “Reset this PC” is the quick method without a USB stick; an installation from a USB stick is more thorough.
• Microsoft continues to offer the Media Creation Tool for Windows 10 for download.
• Back up your data beforehand and check whether you need your product key.
• After installation, check activation and ESU enrolment.

Reset or clean installation?

Windows 10 offers two routes to a fresh system. Which one is right depends on how thorough you want to be and whether Windows still starts.

Resetting is convenient but may bring back pre-installed manufacturer programs. A clean installation from a USB stick starts with a completely empty drive and is also suitable if Windows no longer starts at all.

Preparation

1. Back up your data: Copy documents, photos, emails and browser bookmarks to an external hard drive or to cloud storage.
2. Clarify your licence: If Windows was already activated on this PC, Microsoft generally recognises the hardware after the clean installation and activates it automatically. Our guide Finding your Windows product key explains how to find your existing key.
3. Check your Microsoft account: If the digital licence is linked to your Microsoft account, this makes activation easier after a hardware change.
4. Note down login details: Have passwords for Wi-Fi, email and important programs to hand.
5. Get a USB stick: You need an empty stick with at least 8 GB. Its contents will be completely erased.

Option 1: Reset this PC

1. Open Settings → Update & Security → Recovery.
2. Under “Reset this PC”, click “Get started”.
3. Choose “Keep my files” or “Remove everything”.
4. Decide between “Cloud download” and “Local reinstall”. Cloud download fetches fresh installation files from Microsoft and helps if local system files are damaged.
5. Check the summary and start the process with “Reset”.

If you want to sell the PC, choose “Remove everything” and, in the additional settings, the option to clean the drive. This takes longer but makes it harder to recover your data.

Option 2: Creating a USB stick with the Media Creation Tool

For a clean installation, you first create a bootable USB stick. You can find the right tool on Microsoft's Windows 10 download page.

1. Download the Media Creation Tool using the “Download now” button and run it.
2. Accept the licence terms.
3. Select “Create installation media (USB flash drive, DVD, or ISO file) for another PC”.
4. Choose the language, edition and architecture. For current PCs, 64-bit is the right choice.
5. Select “USB flash drive” and then choose your stick.
6. Wait until the tool has downloaded Windows 10 and written it to the stick.

If you visit the download page from a Mac or Linux computer, Microsoft offers the ISO file directly instead of the tool.

Reinstalling Windows 10 from the USB stick

1. Insert the stick and restart the PC.
2. Open the boot menu. Depending on the manufacturer, you can reach it straight after switching on with F12, F11, F8 or Esc. Select the USB stick there.
3. Select the language, time and keyboard layout and click “Install now”.
4. Enter your product key. If you are installing on a PC that was already activated, click “I don't have a product key”. Activation will then take place automatically later.
5. If asked, select the edition that matches your licence, i.e. Home or Pro.
6. Accept the licence terms and select “Custom: Install Windows only (advanced)”.
7. Delete the partitions on the system drive until only “Unallocated Space” remains. Be careful not to delete any data drives.
8. Select the unallocated space and click “Next”. Windows creates the necessary partitions itself.
9. The installation now runs through with several restarts. Remove the stick as soon as setup begins.

Setup and activation

After installation, Windows guides you through the initial setup with region, keyboard, network and user account. If you are planning to use ESU with the free enrolment in the EEA, it is best to set up the PC with your Microsoft account straight away.

You can see the activation status under Settings → Update & Security → Activation. If you did not enter a key during installation, enter it there via “Change product key”. If you receive error messages, our guide Activating Windows covers the most common error codes.

If you do not have a valid licence, for example after replacing the motherboard or with a used PC, you need a new key for the matching edition. Our guide Buying a Windows 10 key shows what to look out for.