Why Can't I Activate Windows?

Activation ensures that your copy of Windows is genuine and hasn’t been installed on more devices than permitted by the Microsoft Software License Terms. If you receive a message indicating that Windows can't be activated, several factors could be responsible.

Choose any of the topics below to explore common reasons for activation issues and potential solutions to resolve them.

• Missing product key or digital license
• A different key or version of Windows was used during repair
• Once copy of Windows was installed on multiple PCs
• Counterfeit software
• A pre-owned PC
• Hardware changes

Missing product key or digital license

Resolution: Windows activation requires either a 25-character Windows product key or a Windows digital license. 

A different key or version of Windows was used during repair

Resolution: If your PC has been repaired or rebuilt, it’s possible that a different version of Windows was installed. Alternatively, if a different product key was used during the repair, it might have exceeded the number of allowed activations according to the Microsoft Software License Terms.

If Windows was activated before the repair or rebuild, try reinstalling the original version of Windows and re-entering the product key that came with your PC or original copy of Windows.

Once copy of Windows was installed on multiple PCs

Resolution: If you have installed a single copy of Windows on multiple PCs, activation may fail. This occurs because the product key has been used on more devices than permitted by the Microsoft Software License Terms.

To activate additional PCs, you will need to purchase a new product key or a separate copy of Windows for each one.

Counterfeit software

Resolution: Activation is only possible with genuine copies of Windows. A counterfeit copy is one that wasn’t published or licensed by Microsoft.

The Microsoft How to Tell website can help you verify if your copy of Windows is genuine or counterfeit. If your copy is counterfeit, you will need to purchase a genuine copy of Windows.

A pre-owned PC

Resolution: If you purchased a PC with Windows pre-installed, the seller might have used the product key on more PCs than permitted by the Microsoft Software License Terms.

If these aren’t available, or if you’ve used them and still can’t activate your PC, you will need to purchase a new product key or a new copy of Windows. In this case, you may contact one of our Keyzing Support to help you with purchasing a new product key or browse through our FAQs for more information. 

Hardware changes

Resolution: If you made substantial hardware changes to your PC, such as replacing your hard drive or motherboard, Windows might no longer be activated. For Windows 10 and 11, you can add your Microsoft account to help you reactivate Windows after making a hardware change.