How to fix error 0x803D0000 − Windows 10, Windows 8.1

Registering the DNS from the CMD can help with fixing the error code. To register the DNS, follow the steps below:

1. Right-click the start menu, and select Command Prompt (Admin);
2. Type ipconfig /registerdns, and press enter;
3. Restart your computer.

What you can try first if the error 0x803D0000 appears is to turn off your computer and turn it back on, as in most cases it is exactly what you need to do to fix this error.

If you use a desktop computer, you can just unplug it from the power cord and plug it in after a couple of minutes, whereas if you use a laptop remove its battery and reinsert it after a minute.

The Windows Update Troubleshooter tool can help you fix error 0x803d0000, as it will scan your computer for anomalies and direct you to the best approach to fixing them.

To run the tool, follow the steps below:

1. Click on the start menu, go to Settings and click on Update & Security;
2. Click on Troubleshoot and then on Windows Update Troubleshooter;
3. Run the tool and follow the on-screen instructions.

It is possible that the DNS settings became corrupt. resulting in error 0x803D0000. If corrupt DNS was indeed the issue, you need to flush the DNS.

To flush the DNS, feel free to follow the steps below:

1. Right-click the start button (the Windows logo in the lower-left corner) and select Command Prompt (Admin);
   * Alternatively, click the start menu icon and type cmd in the start menu search box, right-click CMD and select Run as Administrator;
   
   
2. When asked whether to allow Command Prompt to make changes to your computer, select Yes;
   
3. Type ipconfig /flushdns and press enter;
4. Restart the computer
   
   

It is possible that a malicious software infected your computer, damaged Windows files, and led to Windows error 0x803D0000. Scan your computer for viruses, using an antivirus or antimalware software and remove them, if detected.

Learn more about how to protect your computer and how to clean it from viruses and other forms of malicious software, via the Computer virus protection guide.

The current firewall and antivirus setup can be the reason behind the error 0x803D0000. To determine if this is the reason, disable the firewall and the antivirus, and see if the error message appear. If it doesn't, go through the firewall and the antivirus settings, and make changes, if needed.

To deactivate the Windows Firewall:

To activate the Windows Firewall:

Maybe the reason behind the Windows error 0x803D0000 is a program which is blocked by the Firewall from accessing the internet, for some reason. In this case, although not fully advised because the Firewall may have considered the program dangerous, you need to grant that program permission to use your Internet connection. To grant it permission, feel free to follow the steps below:

1. Open the start menu and type Allow an app through Windows Firewall;
2. Find the program and tick the check boxes next to it in the Private and Public columns;
3. Click on OK;
4. Restart your computer.

If none of the other solutions helped you fix error 0x803D0000, reinstall the device's operating system. Before you reinstall it, make a backup of your personal data (pictures, music, videos and other invaluable documents) on an external hard drive, or on an online backup solutions like Google Drive, OneDrive, etc., to avoid losing them in the process.

Feel free to use the don't know how to install an operating system guide to learn how to (re)install your computer's operating system, safely.