If the motherboard was kept, Windows should usually reactivate on the same device. Start with the built-in activation flow:
- Open Start > Settings > System > Activation.
- If Windows is not activated, run Troubleshoot.
- If the troubleshooter offers Activate Windows, select it.
- If it shows a hardware-change option, select the path to reactivate after a hardware change.
If a product key was previously used on this device:
- Go to Start > Settings > System > Activation.
- Select Change product key.
- Enter the 25-character product key.
If the issue is caused by the wrong edition being installed, the troubleshooter can detect a valid digital license for a different edition and provide instructions to install the correct edition.
If significant hardware changes are detected, Windows may no longer find a matching license. Microsoft’s reactivation path requires being signed in with the same Microsoft account that was used before the hardware change.
Removing old devices from the Microsoft account is not the recommended first step. The supported path is to use Activation > Troubleshoot and, if offered, choose the reactivation option for recent hardware changes.
If the error changes after running the troubleshooter, use the new error code as the basis for the next step. If the code is not listed, contact customer support.
References:
- [Windows 11](https://support.microsoft.com/windows/activation/get-help-with-windows-activation-errors)
- [Windows 11](https://support.microsoft.com/windows/activation/using-the-windows-activation-troubleshooter#you-have-a-digital-license-for-windows-11-pro,-but-windows-11-home-is-installed)
- [Windows 11](https://support.microsoft.com/windows/activation/reactivating-windows-after-a-hardware-change)
- Why can't I activate Windows? | Microsoft Support