How to fix
KB5012599 failed to install
on Windows

Hello. I have been trying to install the Windows 10 update KB5012599 but it fails every time. I receive an error code 0x800f0831. What should I do?

The 0x800f0831 error code was reported to appear after trying to install the KB5012599 Windows 10 update. People that experience the issue say that the update package downloads successfully but the installation process fails and produces an error message. Microsoft releases important feature updates and security patches[ref en-1] so an update error is a problem that needs to be fixed.

The KB5012599 package is said to make quality improvements to the servicing stack. It can fail to install for a number of reasons. Most of the time, the error is caused by system file corruption, malfunctioning Windows update components, or the SoftwareDistribution folder. Usually, the updating process can be restored by running a built-in update troubleshooter or resetting the update components.

You can also use a maintenance tool like [d1] that can fix most system errors, BSODs,[ref en-2] and registry[ref en-3] issues. It can also automatically clear the system from cookies and cache which are often the culprits of many malfunctions. This powerful software will help you avoid a lengthy troubleshooting process. Otherwise, follow the step-by-step guide provided below carefully.

Solution 1. Run the Update Troubleshooter

• Press the Windows + X keys and go to Settings
• Go to Update and Security
• Click Troubleshooter
• Select Additional troubleshooters
• Run the Update troubleshooter

• Restart

Solution 2. Repair Corrupted System Files

Use Command Prompt commands to repair system file corruption:

• Open Command Prompt as administrator
• Use the following command and press Enter:
  sfc /scannow

• Reboot your system
• If SFC returned an error, then use the following command lines, pressing Enter after each:
  DISM /Online /Cleanup-Image /CheckHealth
  DISM /Online /Cleanup-Image /ScanHealth
  DISM /Online /Cleanup-Image /RestoreHealth

Solution 3. Reset Windows Update Components

• Open Command Prompt as administrator again
• Copy and paste the following commands, pressing Enter after each:
  net stop bits
  net stop wuauserv
  net stop appidsvc
  net stop cryptsvc
  Del “%ALLUSERSPROFILE%\\Application Data\\Microsoft\\Network\\Downloader\\*.*”
  rmdir %systemroot%\\SoftwareDistribution /S /Q
  rmdir %systemroot%\\system32\\catroot2 /S /Q
  regsvr32.exe /s atl.dll
  regsvr32.exe /s urlmon.dll
  regsvr32.exe /s mshtml.dll
  netsh winsock reset
  netsh winsock reset proxy
  net start bits
  net start wuauserv
  net start appidsvc
  net start cryptsvc

• Restart your PC

Solution 4. Delete the SoftwareDistribution Folder

• Search the taskbar for C:\\Windows\\SoftwareDistribution
• Select all the files inside the folder and deleted them

Solution 5. Update via Media Creation Tool

• Download Windows 10 installation media from the official Microsoft website
• Open the tool once it installed
• Agree to license terms
• Choose Upgrade this PC now

• Wait for the update to be installed