In short: plug in a USB drive of at least 8 GB, download the Media Creation Tool from Microsoft's official Windows 11 download page and let it prepare the drive (20 to 40 minutes depending on your connection). Then boot the PC from the drive, choose the edition that matches your licence and follow the setup. On a PC that was already activated, Windows 11 reactivates on its own at the end.
What you need
- A USB drive of at least 8 GB. Everything on it will be erased.
- A Windows PC with internet access to prepare the drive (it can be another computer).
- A backup of your files if you are reinstalling an existing machine: a clean install wipes the disk.
- Your product key if the PC has never been activated on Windows 10 or 11.
Step 1: prepare the USB drive
- On Microsoft's website, open the Windows 11 download page and, under "Create Windows 11 Installation Media", click Download.
- Run the tool, accept the terms, and keep the suggested language and edition (the media contains both Home and Pro).
- Choose USB flash drive, select your drive and let the tool download and copy Windows 11.
Never download Windows from a third-party site: a modified file can contain malware. A reputable seller always points you to Microsoft's servers.
Step 2: boot from the USB drive
Plug the drive into the PC you are installing, switch it on and immediately press the boot menu key: often F12 (Dell, Lenovo, Acer), F9 (HP), Esc (Asus) or F11 (MSI). Pick the USB drive from the list. If it does not appear, check in the BIOS that UEFI boot is enabled.
Step 3: install Windows 11
- Choose your language and keyboard, then Install Windows 11.
- On the product key screen, enter your key, or click I don't have a product key if the PC was already activated: the digital licence will be recognised after setup.
- Select the edition that matches your licence: Home or Pro. A mistake here will prevent activation.
- For a clean install, delete the partitions on the old system disk, select the unallocated space and click Next. Do not touch other disks.
- At the end, connect to the internet and sign in with your Microsoft account (required for personal use).
Step 4: check activation
Open Settings > System > Activation. If the PC was previously activated with the same hardware, the status shows "Active" after a few minutes. Otherwise, click Change product key and enter it: details and error codes are in our guide Activate Windows 11 with a product key.
Reinstall without a USB drive: "Reset this PC"
If Windows still starts, Settings > System > Recovery > Reset this PC reinstalls Windows 11 while keeping or removing your personal files. Activation is kept and no key is requested. The Cloud download option fetches a fresh copy of Windows from Microsoft, useful if the system is damaged.
Frequently asked questions
Will I lose my licence by reinstalling Windows 11?
No. On the same PC, Windows 11 reactivates automatically thanks to the digital licence stored by Microsoft, provided you install the same edition (Home or Pro).
What size USB drive do I need?
At least 8 GB. A 16 GB USB 3.0 drive makes preparation and installation noticeably faster.
Can I create the drive from a Mac?
The Media Creation Tool only runs on Windows. From a Mac, the easiest option is to prepare the drive on another Windows PC.
Does the USB drive install Home or Pro?
Both. The edition is chosen during setup or deduced from your product key. You then need a licence for the same edition to activate.
Need a licence for your installation? Our Windows 11 Home and Pro keys are delivered by email within minutes, with Microsoft's official download link and an invoice.