Follow these steps in order.
- Check if Windows is already activated
- Select Start > Settings > System > Activation.
- Under Windows, check the activation state.
- If it shows Active, Windows is already activated.
- If it shows Not active or an error, continue with the next steps.
- Try automatic activation (Windows 10/11)
- Make sure the PC is connected to the internet.
- Stay on Settings > System > Activation and wait a few minutes so Windows can try to activate online.
- If activation still fails, select Troubleshoot (if available) to run the Activation troubleshooter. It will run diagnostics and attempt to fix common activation problems.
- If activation errors continue
- Open the search box on the taskbar, type winver, and select Winver to confirm the version and build of Windows.
- If running Windows 11, follow the guidance in Get help with Windows activation errors:
- Confirm Windows is up to date (install all Windows Updates).
- Run the Activation troubleshooter again from Settings > System > Activation.
- If an error code appears, follow the steps for that code in the activation errors article.
- Activate Windows 11 using the internet
- If the device is already on Windows 11 and has a valid license, it should activate automatically when online.
- To confirm:
- Go to Start > Settings > System > Activation and check under Windows.
- Activate by phone if online activation fails
- Go to Start > Settings > System > Activation.
- Under Activate Windows now, select Activate by phone.
- Follow the on-screen instructions to use the Product Activation Portal or call the provided number.
- If using a pre-owned PC or after hardware changes
- If the PC was bought used and activation fails, the previous owner may have used the same product key on more devices than allowed. In that case, a new product key or a new copy of Windows is required.
- If major hardware changes were made (for example, motherboard replacement), link the Windows license to a Microsoft account and use the Activation troubleshooter to reactivate after the change.
- Upgrading to Windows 11
- First ensure the current Windows installation is activated.
- Then use Windows Update or the official Windows 11 installation path to upgrade. After upgrade, Windows 11 should automatically activate if the license is valid.
If updates appear to be stuck “updating” and never complete, allow updates to finish first, then re-check activation as above. If activation errors persist and are not listed in the activation errors article, contact Microsoft customer support from the activation error page.
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