[Solved] Microsoft Office Activation Error 0X4004F00C in Windows 10

Several Microsoft Office users reported an Activation Error 0X4004F00C when using an Office Suite program such as Word, PowerPoint, Excel, or others. This problem can occur due to having different problems like interference with VPNs or Proxy and corrupted Office installation. If you’re also facing such an issue while using a Microsoft Office product then this article may help you fix it.

This article includes five potential workarounds that can assist you to complete the activation process easily and continue using the Office Suite. 

How to Fix Microsoft Office Activation Error 0X4004F00C

You can use the following workarounds to fix Microsoft Office Activation Error 0X4004F00C on your PC.

1. Run the Office Activation tool

Running the Office Activation tool has been reported to work by several affected Windows users. This method requires you to download a compatible Office Activation troubleshooter (Microsoft 365, Office 2016, 2019, or 2013) and use it to fix the error. You can follow the below steps if you want to go with this solution.

• To run the Office activation tool, you first need to download either Microsoft 365, Office 2016 & Office 2019, or Office 2013 depending upon which version currently you’re using.
• After downloading it, go to the downloading location and open the .exe / .diagcab file.
• When UAC appears on the screen, click Yes to grant administrative privileges.
• On the next screen, click on the Advanced menu and then tick the Apply repairs Automatically box and then click the Next button. Wait for a while until it scans the initial state.
• If a viable fix is detected, it will be applied automatically.
• On the next screen, click the Apply this fix option and then follow the on-screen guidelines.

Once you perform the procedure, restart your computer. And then open the Office app and see if the problem is fixed now.

2. Disable your Proxy Server

Disabling the Proxy server helped many users to get rid of this issue. The procedure to turn off the Proxy server is following:

• Right-click on Start and select Settings > Network & Internet > Proxy. You can also type “ms-settings:network-proxy” in the Run dialog box to open the Proxy tab directly.

• Inside the Proxy tab, scroll down to the Manual proxy setup section and then turn the toggle button off related to Use a proxy server.

After disabling the Proxy server, restart your computer and try to do the activation once again. If the error code 0X4004F00C still persisting, continue to the next working solution. 

3. Uninstall the VPN Connection

If you’re using any third-party VPN connection then uninstalling it might be helpful. So, remove the active VPN through the Control Panel or Windows Settings and see if it works.

• Open the Run dialog box using Windows + R keys.
• Type “appwiz.cpl” in the text box and press Enter.
• In the Program and Features window, look for the VPN that might be causing the issue.
• Right-click on the problematic VPN and select the Uninstall button. Now follow the on-screen guidelines to complete the process. 
• After uninstalling the VPN, restart your computer and this should solve the problem now.
• If you’re still encountering this issue, continue to the next method.

4. Turn Windows Defender Firewall off

Windows Firewall and other 3rd-party firewalls might be another possible culprit to cause this issue on your device. This problem mainly occurs due to a false positive. In such a case, you can disable the Windows Defender Firewall (or a similar third-party firewall) and see it works.

• Open the Control Panel window.
• In the Control Panel window, set the View by as Large icons.
• Now select the Windows Defender Firewall item.
• Go to the left and select Turn Windows Defender Firewall on or off.

• Under Private network settings, check the Turn off Windows Defender Firewall (not recommended) checkbox.
• Similarly, go to the Public network settings section and turn off the Firewall.
• Click on the OK button to save the changes and exit.

Once you apply the above actions, it should probably fix your problem. But, if it doesn’t work, you can follow the below steps to disable the third-party firewalls.

• Right-click on the Start button and select Apps and Features.
• In the Settings app, go to the right pane and locate the 3rd party firewalls if it is installed.
• Once you find it, select it and then click the Uninstall button.
• If UAC appears on the screen, click the Yes button to grant administrative privileges.
• Then follow the on-screen instructions to complete the uninstalling procedure.

Once you complete, restart your computer and try to activate your Windows.

5. Reinstall the Office Installation

If none of the above solutions help you to fix out this error, you can try reinstalling the Office installation and check for the error code. 

• Click on Start, type “Control Panel”, and then select the same from the search result.
• Select the Program and Features option from the available item list.
• In the Program and Features window, right-click on the Office installation and select Change from the context menu.
• Select the Online Repair option to repair the Office program. Wait for a while until it completes the process.
• To complete the repairing process, follow the on-screen guidelines.
• Restart your device if you’re asked to do so.

After following the above guidelines, check if the problem is solved now.