Fix: Windows Activation Error Code 0xC004C008

Some Windows users have been reporting that their activation attempts fail with the error code 0xC004c008. The issue is reported to occur on Windows 7, Windows 8.1 and Windows 10.

Windows activation error 0xC004c008

Note: This article is only relevant in those situations where the Windows copy affected by the error code is genuine.

What is causing the ‘0xC004c008’ error code?

We investigated this particular issue by looking at various user reports and the repair strategies that are commonly used to resolve this error code.

Based on our investigations, it turns out that this error code is associated with an issue with the product key. As it turns out, there are a couple of scenarios that will trigger this particular error code:

  • The product key is being used on another PC – Typically, Windows 10 and Windows 8.1 licenses can only be installed on a single device. If the license is actively being used on another computer, you’ll receive this error code until you’ll resolve the conflict.
  • The KMS key is being used on more PCs than allowed by the Software License Terms – This issue might also occur if the KMS key has exceeded the activation limit. If you’re dealing with a KMS key, know that you can only activate it up to 10 times on six different computers.

If you’ve purchased your Windows copy from a genuine retailer and you’re struggling to resolve this particular error code that appears when you try to activate your Windows version, this article will provide you with several troubleshooting steps.

Down below, you’ll discover a collection of methods that other users in a similar situation have successfully used to avoid the error code and activate their Windows version. You should be able to follow every method regardless of your OS version, so feel free to follow whichever method seems more convenable to you.

Let’s begin!

Method 1: Using the Activation Troubleshooter (Windows 7 only)

Instances where you didn’t hit any restrictions related to your particular licensing, can typically be corrected by simply running the Activation Troubleshooter. This built-in tool contains a collection of repair strategies that will automatically resolve the issue with specific situations like re-installing the OS from a recovery environment or booting from a cloned drive from the first time on a different configuration.

Using this troubleshooter will most likely resolve the issue if you’ve encountered the 0xC004c008 after making a significant change such as replacing the motherboard or reinstalling Windows.

Note: But keep in mind that the procedure below is only applicable if you’re getting the error with Windows 10.

Here’s a quick guide on how to use the Activation troubleshooter:

  1. Press Windows key + R to open up a Run dialog box. Then, type “ms-settings:activation” and press Enter to open up the Activation tab of the Settings screen.
    Accessing the Activation troubleshooter
  2. Once you get into the Activation tab, move over to the right pane, scroll down to the Activate Windows now menu and click on Troubleshoot.

    Accessing Activation Troubleshooting
  3. Leave the troubleshooter to investigate for problems, then click on Apply this fix if any issues are uncovered.
  4. Once the procedure is complete, restart your computer and see if your Windows is re-activated at the next startup.

If the issue is still not resolved or this method wasn’t applicable to your particular scenario, move down to the next method below.

Method 2: Using phone activation

If you purchased the key from a genuine retailer, you should be able to use phone activation to get your Windows version activated.

In most cases, you should be able to see a Phone Activation option inside the Activation window (in Windows settings). To get there, press Windows key + R to open up a Run dialog box. Then, type ‘ms-settings:activation‘ for Windows 10 or ‘slui’ for an Older Windows version and press Enter to open the activation menu.

Windows 10 phone activation

If you don’t see a “Phone Activation” option inside the Activation window, press Windows key + R (to open a Run box) and type “SLUI 4” to bring up the phone activation menu (works on every Windows version.  Then,  choose your Country from the list and click on Phone Activation.

Once you see the phone activation screen, simply call the number provided there and use the automated system as instructed. You will need to provide your own installation ID (displayed inside the Phone Activation screen) and after the verification is complete, your Windows will be activated.

If this method wasn’t applicable or you’re looking for a different approach, move down to the next potential workaround below.

Method 3: Contact a Microsoft Agent

If resolving the issue with the built-in Activation troubleshooter or with phone activation where not applicable to your particular scenario, then you’re left with little else choice but to contact Microsoft chat support and ask them to help you with the reactivation.

There are multiple ways to do so, but the easiest one is to simply follow this link (here), open the Get Help app and wait for a live agent to arrive in the chat and assist you with your situation.  Several affected users reported that contacting an MS live agent helped them to resolve the issue in a matter of minutes.

But remember that this is only applicable if your Windows copy is genuine and you haven’t violated any of the Software License Terms related to your Windows license.


Kevin Arrows

Kevin Arrows is a highly experienced and knowledgeable technology specialist with over a decade of industry experience. He holds a Microsoft Certified Technology Specialist (MCTS) certification and has a deep passion for staying up-to-date on the latest tech developments. Kevin has written extensively on a wide range of tech-related topics, showcasing his expertise and knowledge in areas such as software development, cybersecurity, and cloud computing. His contributions to the tech field have been widely recognized and respected by his peers, and he is highly regarded for his ability to explain complex technical concepts in a clear and concise manner.