0xc004c020: How to Quickly Fix This Activation Error

The 0xC004C020 activation error occurs within organizations

by Loredana Harsana
Loredana Harsana
Loredana Harsana
Managing Editor
Loredana is a passionate writer with a keen interest in PC software and technology. She started off writing about mobile phones back when Samsung Galaxy S II was... read more
Reviewed by Alex Serban
Alex Serban
Alex Serban
Windows Server & Networking Expert
After moving away from the corporate work-style, Alex has found rewards in a lifestyle of constant analysis, team coordination and pestering his colleagues. Holding an MCSA Windows Server... read more
Affiliate Disclosure
  • Windows activation error 0xc004c020 occurs when the MAK (Multiple Activation Key) is overutilized on organization-managed computers.
  • To fix this error, you must activate the key through Command Prompt.
  • You can always contact Microsoft for Windows activation issues.

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Many of our readers have reported the error 0xC004C020 while trying to connect their computers to their organization’s server. This error prevents to activation of their Windows operating system.

While the error can be frustrating, we will guide you toward resolving the error 0xC004C020 while trying to activate Windows on organization-linked computers.

What causes the error 0xC004C020?

If you are trying to activate Windows on your organization-linked computer and encounter the error 0xC004C020, then the possible causes could be as follows:

  • Non-MAK key – If a non-MAK key is used on an organization-linked computer, then the organization’s policy will not allow its activation.
  • Key access lost after formatting – Multiple Activation Keys can be used only once. If the computer is formatted, you cannot repeat the key by yourself.
  • Wrong activation key – It could be possible for the activation key to be incorrect. This has to be verified with the system administrator.
  • MAK key usage limit crossed – Windows keys used by organizations have a limit on the number of systems on which they can be used. If this limit is exceeded, the key won’t work.

Now that we know the reasons behind the problem, let us try to fix it.

How do I fix the 0xC004C020 activation error on Windows?

Before proceeding with the troubleshooting involving your organization, you could try a few quick solutions:

  • Re-check the key you are typing and make sure it is correct.
  • Make sure your computer is connected to the organization’s network.
  • Restart your computer.
  • Contact the IT Server Administrator.

If the preliminary solutions were not helpful, please proceed with the following solutions sequentially.

1. Activate Windows using Command Prompt

  1. Click the Search icon on the taskbar, type command prompt, and click on Run as administrator from the results to start Command Prompt with full privileges.  
  2. Type the following command and hit Enter to execute the command (replace [product key] with the actual product key): slmgr.vbs /ipk [product key]

Windows systems should pick the activation key automatically, but if it doesn’t, the Command Prompt method can be helpful.

2. Run the Windows Activation troubleshooter

  1. Right-click on the Start button and select Settings from the menu. In the Settings menu, go to the System tab in the left pane.
  2. In the right pane, select Activation.
  3. If your Windows operating system is not active, then you will notice a button named Troubleshoot. Click on Troubleshoot to run the troubleshooter.
  4. The Windows Activation troubleshooter will pick up the key if it was deactivated after recent system changes.

3. Activate Windows through phone

  1. Right-click on the Start button and go to Settings.
  2. Go to System and select Activation.
  3. You will notice the option to Activate Windows Now. Under it, click on Activate by Phone.
  4. Select your country and click on Next.
  5. You will notice an Installation ID and freephone number. Call the freephone number to get the Confirmation ID.
  6. Enter the Confirmation ID and select Activate Windows.

These solutions should help you fix the activation error, but if not, you can always contact Microsoft support. Feel free to check our generic guide on solving general Windows activation issues.

If your problem persists, please let us know in the comment section. We will check for further solutions.

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