Let us look how to remove the error windows activation key error 0xc004c003. With the support of our Server management support services at Bobcares we will now go through the whole setup process.

Error: windows activation key error 0xc004c003

Assume that we recently updated to Windows 11 or restored the operating system, and we are experiencing a Windows activation failure with the error code 0xc004c003. This problem typically happens when the system attempts to activate the operating system using an OEM Activation Digital Product Key.

Here are a few troubleshooting solutions to assist us in resolving this difficulty and activating the copy of Windows 11.

Causes of Windows 11 Pro Error Code 0xc004c003

In Windows, the licensing code component is in charge of accessing the registry hive and confirming the product key. When access is disallowed owing to inappropriate access, the 0xc004c003 error occurs.

This error can be caused by a failing key validation, however the causes for the failure can vary. In this section, we will look at a couple fixes for this problem with Windows 11.

Solution: Windows 11 Pro Error Code 0xc004c003

The installed OS edition may differ depending on how we installed Windows 11 on the PC. If we did an in-place update, Windows would recognize the existing edition and install the appropriate edition.

But, if we did a clean install of Windows 11, we may have installed the Pro edition instead of the Home edition. We will be unable to activate the Pro edition with a Home edition license key.

To determine the Windows 11 edition that is currently installed:

1. To open Settings, press Win + I.
2. Go down and click on About on the System tab.
3. Go down to the Windows specification section in the right pane. Locate the Edition area to see the Windows 11 edition that is installed on your computer.
4. If the Windows 11 edition is the same as the previous edition, skip to Fix three below.

If we purchased a Windows 11 Home license key and installed the Pro edition, we can downgrade.

Revert from Windows 11 Pro to Windows 11 Home

If we use the Home edition license key to upgrade to the Pro edition of Windows 11, we will get the activation problem 0xc004c003.

There are two approaches to this problem: To begin, either purchase the Pro version or downgrade to the Home edition.

If we don’t want to spend money on a new upgrade, we may downgrade from Windows 11 Pro to Home in two stages. We must first modify the registry editor in order to prepare for the downgrade, and then execute the ISO setup file to finish the procedure.

Modifying the Registry in Order to Install Windows 10 Home

1. To open Run, press Win + R.
2. To open the Registry Editor, type regedit and press OK. When asked by the UAC, select Yes.
3. Go to the following place in the Registry Editor. To make navigating simpler, copy and paste the route into the Registry Editor:

   Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
4. Locate and double-click the ProductName value in the right pane.
5. Enter Windows 11 Home Single Language in the pop-up window.
6. To save the changes, click OK.
7. Next, find and double-click the EditionID value.
8. Enter CoreSingleLanguage in the pop-up box.
9. To save the changes, click OK.
10. Next, in the Registry Editor, browse to the following location:

    Computer\HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion
11. In the right pane, look for the ProductName value and change it to Windows 10 Home.
12. Click OK to save the changes.
13. Next, locate and double-click on the EditionID and change it to CoreSingleLanguage.
14. Click OK to save the changes.
15. Close the Registry Editor

Install Windows 11 Home

We will download the ISO file and execute an in-place update to finish the downgrading procedure. An in-place upgrade allows us to reinstall Windows without having to remove any data or applications. Here’s how to go about it.

1. Go to the Microsoft Windows 11 download page.
2. Go down to the section titled Download Windows 11 Disk Image (ISO).
3. Choose Windows 11 from the drop-down menu.
4. Choose the Download option.
5. Next, from the drop-down menu, pick the language.
6. Hit the Confirm button.
7. Choose the 64-bit Download option. That will begin the download of Windows 11 ISO.
8. Open the download folder after the ISO has been downloaded.
9. Mount the ISO picture by right-clicking it.
10. Windows will immediately mount the ISO and access the drive folder. If not, choose the DVD Drive icon from the This Computer menu.
11. Double-click the Setup.exe file within the ISO drive. If UAC prompts us, select Yes.
12. Alter how Setup downloads updates in the Install Windows 11 dialog.
13. Then, choose Not right now. To proceed, click Next.
14. Accept the notifications and licensing conditions after that.
15. Make sure the Install Windows 11 Home and Maintain personal data and programs option is selected in the Ready to install window.
16. Wait for the procedure to finish before clicking Install.
17. Depending on the system hardware, an in-place upgrade may take several hours to complete. We may see a few reboots throughout the process, but this is typical.

Check to see if the downgrade was successful after restarting. To do so, go to Settings > About > Windows Specs and choose Edition.

Go to Settings > System > Activation to activate Windows 11. Next, follow the on-screen steps to activate your Windows 11 version.

Using the Command Prompt, activate Windows 11

Due to service difficulties, the Microsoft server may occasionally fail to validate and activate your license. If the activation continues to fail, you can utilize the Command Prompt to activate your license. Here’s how to go about it.

1. Type cmd into the Windows key.
2. Right-click on Command Prompt in the search results and select Run as administrator. If UAC prompts us, select Yes.
3. Enter the following command in the Command Prompt window:

   –slmgr.vbs –rearm
4. When the success prompt appears, click OK and restart your computer. After restarting, go to the activation page and see if the 0xc004c003 error has been fixed.

To reactivate Windows after a hardware change, contact Microsoft

When we initially register the Windows 11 license, it identifies itself with the computer’s hardware. This allows Microsoft to guarantee that the license is used in accordance with the conditions of use, and it also saves the user from having to manually activate Windows after a clean install.

But, if we have made significant hardware modifications, such as upgrading the motherboard, Windows will be unable to validate the data. We can fix this by using the Digital Product Key or running the troubleshooter to validate and activate Windows.

Fixing Windows 11 Activation Error 0xc004c003

For devices with inactive Windows licenses, Microsoft disables some customisation and other functions. To troubleshoot the problem, check your Windows 11 version and product key, or use the Command Prompt to manually activate the key.

We may also wish to check the validity of the license and, if necessary, downgrade to the right edition of Windows 11.

If nothing else works, consider downgrading from Windows 11 to Windows 10 while Microsoft irons out the early issues and quirks.

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Conclusion

To sum up we have now gone through a detailed guide on how to remove the erro windows activation key error 0xc004c003. WIh the support of our Server management support services at Bobcares we have seen the whole process.