Did you recently encounter Windows Activation Error Code 0xC004C008 on your computer screen? If so, then this post will help you to fix this issue. This problem generally occurs when you install, update, or upgrade your Windows 11/10. It indicates the Windows 11/10 product key you are using may have been used on multiple devices. In this article, we have explained the possible workarounds that can certainly help you to resolve this issue.

With this Activation error, you could see an error message saying

0xC004C008, The activation server determined that the specified product key could not be used.

Sometimes you may see a different error message:

The activation server reported that the product key has exceeded its unlock limit. (Error code: 0xC004C008)

Windows Activation Error Code 0xC004C008

The error occurs if the product key which you are trying to use has already been used on a different PC, or it is being used on more than one PC than the Microsoft Software License Terms allow. Fix this activation problem by buying a product key for each one of your PCs in order to activate Windows on them.

You can buy a product key from the Windows Store by following these steps:

Click on Start and then select Settings > Update & security > Activation.
Choose Go to Store, and follow the shown instructions to buy Windows.

If that doesn’t not help, then follow the below suggestions to get rid of this issue:

Try the Activation troubleshooter
Use Phone Activation
Contact Microsoft Customer Support

Let us now see them in details:

1] Try the Activation troubleshooter

If this problem has occurred due to having some type of licensing restriction, then you can try the built-in Activation troubleshooter tool to fix it. Follow the below steps to do it:

First of all, open the Windows Settings using the Win+I keyboard shortcut.
Once it opens, click on Update & Security > Activation tab. Go to the right side and click on the Troubleshoot.
Then select the ‘Apply this fix’ option to perform a repair strategy.

Once you have done, reboot your computer and check if Activation error code 0xC004C008 is solved.

2] Use Phone Activation

Alternatively, you can activate your Windows 11/10 device by Phone. Here is how to do it:

Open the Run dialog box by pressing the Windows key + R. In the text box, type “SLUI 4” and hit Enter.
Select your country from the list of options and click on the Next button.
When the phone activation page opens, try to contact the number available for your country.
Use the automated system properly as instructed.
If you receive a confirmation ID from the automated system, note down it.
Then enter the provided confirmation ID in the box and then hit Activate.

Once you complete the steps, this activation Error should be gone.

3] Contact Microsoft Customer Support

Unfortunately, if none of the above-mentioned methods worked for you and you are still facing the Windows Activation Error code 0xC004C008, then contact Microsoft Support and request them to activate your operating system.

Hope this helps!