How to Repair Error Code 0xA0000400 on Windows PC

Like any other system, Microsoft Windows 10 can have several problems and issues. For example, you may find error code 0xa0000400 when you update your system. Many people want to know how to solve this problem, which is why I am here to write this article. I am going to provide you with some practical solutions that will help you solve Windows 10 error 0xa0000400. Please read them carefully!

What causes error code 0xA0000400?

Problem with the local WU component: If Windows Update doesn’t allow you to automatically install pending feature updates.

Operating system-related system file corruption: In some circumstances, your system may be affected by a corrupted system file that makes a major EMU component inaccessible.

Common WU Problem: It turns out that this particular problem can arise from several common predispositions that make the WU service inaccessible.

Damaged WU boot folder or disabled WU service: If the problem is due to a disabled service dependency or damage to the SoftwareDistribution and Catroot2 folders.

How to resolve error code 0xA0000400?

Perform a system maintenance

  1. Type Control Panel in the search box and press Enter.
  2. In the window that appears, select Small Icons in the category view.
  3. Select Troubleshooting, and then Show All Links in the left pane of the window.
  4. When the next window opens, locate System Maintenance and click Next.
  5. Wait a while for the system to detect the error and fix it.
  6. After that, update your existing operating system.

Launch the Windows Update Troubleshooter

  1. Press the Win and I key combination to launch the Settings application.
  2. Select the Update and Security category, then Troubleshoot in the left pane.
  3. Switch to the right pane and click on Windows Update.
  4. Now click Run Troubleshooting to start the process.
  5. After completing the above steps, restart your computer.

Install Windows 10 update manually

  1. First, visit Microsoft’s update directory.
  2. Type a specific KB number in the blank space and click Search.
  3. A list of cumulative updates that contain the KB number you entered will appear.
  4. Select the update that matches your system architecture and click the Download button next to it.
  5. When the download is complete, double-click the installation file and follow the instructions on the screen to install the latest patch.

Remove unnecessary files with disk cleanup

  1. Right-click on the Windows icon and select execute.
  2. Type cleanmgr and click OK.
  3. Select the root drive (C:) here and type OK again.
  4. On the next page, click the option Clear system files.
  5. Select the C: drive again, then OK to see how much disk space you can free up.
  6. Now check all the boxes except Download and click OK to start the process.
  7. Click Delete Files to confirm the cleanup.

Frequently Asked Questions

You can upgrade your license key to the Pro version. First, open Settings and click Update and Security. Then click Activation and enter your product key for Windows. Try updating your Windows OS again after changing your product key and see if the process completes without the same 0xa0000400 error.

There is a quick solution to get around this error. Since this error is caused by Microsoft's update utility, you can update Windows manually using the Windows Update directory to install the update that produces this error code.

Error code 0xA0000400 is reported by the update wizard (see screenshot below) and indicates that an error occurred during the installation of the Windows 10 update. It is noticeable that the error most often affected users in 2016 in the area of Windows 10 Education version 1607.