What to do if the activation key does not work in Windows 10 and 11

There are several reasons why your Windows activation key might not work on your computer. Here's what to do in this case.

Windows Activation Key (Windows Activation Key) or Product Key (Windows Product Key) is a 25 character code, of the type XXXXX-XXXXX-XXXXX-XXXXX-XXXXX, used to activate Windows either during or after installation on a device.

Can only be used on one computer at a time. However, some users may face problems with the activation key as there are cases where it may not work.

Let's see what to do to fix Windows 10 and 11 product key not working problem.

Confirm your Windows version

Sometimes users buy a digital license or key for the wrong version of Windows. When they try to activate Windows with this key, it will not be accepted. For example, if you try to activate a Windows Pro installation with a Windows Home key, it won't work.

Check your version of Windows and make sure you have the correct key for that version. If you bought the wrong key, request a refund and get the key that matches your version.

Run the Activation Troubleshooter

If you can't activate Windows 11, try running it activation troubleshooter.

Windows 11: Go to Settings > System > Activation > Troubleshoot

Windows 10 : Go to Settings > Update & security > Troubleshoot

If you don't see the troubleshooter, Windows may already be activated. In this case, please check your product key again.

Verify your internet speed

Make sure you have a stable internet connection before activating Windows. If your internet is slow, try restarting your router.

Use a genuine Windows activation key

To activate Windows, you need a genuine product key. No valid activation key, you will not be able to activate Windows on your computer.

There are many fake keys sold by scammers and retailers. Avoid buying keys from questionable sources. Purchase your Windows license from a reputable retailer.

Make sure you only use the activation key on one computer

You cannot use the same license key on more than one computer. If you have already used the key on another device, you should uninstall or remove it from the device before using it on a different computer.

Alternatively, you can purchase a separate key for each computer.

If you have another Windows computer, use the command below to check your product key:
wmic path SoftwareLicensingService get OA3xOriginalProductKey

If Windows has been activated with a digital license, then your operating system is activated without a product key, so there is no key stored on the system to retrieve, and you will only see OA3xOriginalProductKey as a response. If it's activated with a digital license and still gives you a key back, then the computer will have that key stored in the BIOS settings, in the hardware.

If you use the same key on this computer, run the command below to uninstall the key:
slmgr.vbs /upk

Then run the following command to remove the key from the Windows registry.
slmgr /cpky

Confirm Windows activation

If you bought a new computer, Windows may already be pre-installed and activated on your device, which could explain why your activation key isn't working. To check if Windows is already activated:

Open Windows Settings and go to System > Activation. There check the message it gives next to “Activation Status”.

You do not need to activate Windows if the activation status is "Active".

Run an SFC scan

Open Command Prompt with administrator rights. To do this, search for 'cmd' in the Start menu and select 'Run as administrator'.

Type sfc /scannow and press Enter.

Activate Windows

Launch Command Prompt as administrator and type the following command and press Enter:

slmgr /ipk [Windows_key]
Replace [Windows_key] with a valid Windows activation key. Example:
slmgr /ipk FF67G-XXXXXX-4S34J-XXXXXX-LYY0A