Install Windows 10 from an ISO or USB stick

What you need

• Your Windows 10 product key (order confirmation email / Lizensa dashboard)
• An 8 GB or larger USB stick
• A working PC with internet access

Step 1 — Create installation media

1. On a working PC, download Microsoft's Media Creation Tool.
2. Run it, choose Create installation media, pick the language and edition that matches your key (Home or Pro), and write it to the USB stick.

Step 2 — Install Windows

1. Plug the USB stick into the target PC and boot from it (pick the USB device in the boot menu — usually F12, F11 or Esc).
2. Follow the wizard: language and keyboard, then Install now.
3. When asked for a product key, select I don't have a product key and choose the edition that matches your key.
4. Select Custom: Install Windows only, pick your drive, and let the PC restart until the desktop appears.

Step 3 — Activate

1. Open Settings → Update & Security → Activation.
2. Select Change product key, enter your 25-character key, and select Next.
3. Wait for "Windows is activated", then run Windows Update once.

Verify

Run slmgr /xpr in Command Prompt — the license should report as permanently activated.