To use the old laptop again, Windows must be reinstalled and then activated.
- Back up any files if possible
If the laptop still boots at all, copy personal files to an external drive or to a cloud service such as OneDrive before reinstalling, because some reinstall options can remove files.
- Create Windows installation media on another working PC
On a working Windows PC, use the Media Creation Tool to create the installation media for Windows (USB or DVD). This will let the old laptop install or reinstall Windows.
- Boot the old laptop from the installation media
Connect the USB/DVD to the old laptop and start it from that media. If it does not boot from USB/DVD automatically, change the boot order in the laptop’s firmware/boot menu (check the laptop manufacturer’s instructions).
- Choose how to reinstall
- For a completely fresh start (removes files, apps, and settings), follow the Clean install steps from the installation media. During setup, select the edition of Windows that matches the license the device had before (for example, Home vs Pro). A clean install will erase personal files and apps on the laptop.
- If the laptop can still start Windows normally, an in‑place reinstall from within Windows can keep personal files and apps, but this requires being able to sign in first.
- Activate Windows after reinstall
After installation, connect the laptop to the internet. Windows usually activates automatically if:
- The device has a digital license stored with Microsoft’s activation servers, or
- The product key is embedded in the device firmware.
If activation does not happen automatically, use Settings → Update & Security → Activation (or the equivalent in Windows 11) and run the Activation troubleshooter. If there was a significant hardware change or the license is not recognized, support may be needed to reactivate.
If Windows cannot be activated and the laptop is very old, consider the options for staying on a supported Windows version, such as installing Windows 10 or 11 if the hardware meets the minimum system requirements for Windows 10 or Windows 11.
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