If Windows 10 was upgraded to Windows 11 through the free upgrade, activation is typically tied to the device’s digital license. After a reset, Windows should reactivate automatically when the device is online and the hardware matches the license.
Try this in order:
- Check activation status in Start > Settings > System > Activation.
- If Windows is not activated, use the Activation troubleshooter:
- Go to Start > Settings > System > Troubleshoot.
- The troubleshooter is available only when Windows is not activated.
- An internet connection is required.
- Sign in as an administrator before running it.
- Make sure the Microsoft account previously linked to the digital license is being used. Linking the Microsoft account to the digital license is important for reactivation after changes.
- If a product key is available, enter it manually:
- Go to Start > Settings > System > Activation > Change product key.
- Enter the 25-character product key.
- Check that the installed edition matches the license. If the license is for Windows 11 Pro, the installed edition must also be Windows 11 Pro or activation will fail.
- If there was a significant hardware change such as a motherboard replacement, Windows may no longer find a matching license. In that case, use the reactivation guidance for hardware changes.
- If the troubleshooter does not fix it, contact support.
A reset alone should not normally prevent reactivation when the device has the correct edition and the digital license is still associated with the same hardware.
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