How to fix
KB5028948 fails to install
on Windows

Hello. I can't seem to install the KB5028948 update for Windows 11. Is there a way I can fix this?

Users of Windows 11 have lately reported an installation issue with the security update KB5028948.[ref en-1] This update is critical because it fixes critical operating system vulnerabilities, notably those connected to Internet Information Services (IIS) and ClickOnce deployments. This security patch's primary goal is to address a vulnerability in applications that use their parent application's Application Pool on IIS. Exploiting this vulnerability could result in privilege escalation or security bypasses, endangering the system's overall security.

Another vulnerability addressed by KB5028948 is ClickOnce deployments. Unauthenticated remote attackers can exploit this vulnerability to digitally sign ClickOnce deployments without a valid code signing certificate. As a result, they may distribute malicious software that looks to be from a genuine source, duping users into installing dangerous applications on their PCs. This exploit has the ability to distribute malware, jeopardize data integrity, and undermine user confidence in software distribution systems.

Users are recommended to investigate alternate methods to mitigate risks associated with the failure to install KB5028948. One option is to manually apply the security update using the Microsoft Update Catalog or the Windows Update Troubleshooter to fix any underlying installation issues.

In this guide, you will find 6 steps that should help you fix KB5028948 failing to install in Windows 11. You can also run a repair tool like [d1] that can fix most system errors, BSODs,[ref en-2] corrupted files, and registry[ref en-3] issues. Otherwise, follow the step-by-step instructions below.

Method 1. Run Windows Update Troubleshooter

• Click the Windows button and select Settings
• Select System from the left pane, then scroll down on the right pane, and click on Troubleshoot

• Click on Other troubleshooters
• Locate the Windows Update troubleshooter and hit the Run button

Method 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

Method 3. Restart Windows Services

• Type services in the search bar and launch the Services utility
• Find Windows Update in the list
• Double-click on it, set the Startup type to Automatic, and click Apply
• Now click on Restart the Service

• Do the same with Background Intelligent Transfer Service

Method 4. Use the Microsoft Update Catalog

• Go to the official Microsoft Update Catalog website
• Type the KB number KB5028948 into the search bar, and press Enter or click Search

• You will find many different versions on the update – you need to find the one that matches your PC specs and Windows version (as a home user, ignore Windows server versions)
• After picking the correct version, click the Download button and proceed with the on-screen instructions
• Restart your system once done

Method 5. Reset Windows Update Components

• Type cmd in the search bar.
• Right-click on Command Prompt in the search results.
• Select Run as administrator.
• In the Command Prompt window:
• Type the following commands one by one and press Enter after each:

net stop wuauserv

net stop cryptSvc

net stop bits

net stop msiserver

• Execute the following commands one by one:

net start wuauserv

net start cryptSvc

net start bits

net start msiserver

• Restart your PC.
• Check to see if the issue has been resolved.

Method 6. Use Installation Media

If none of the previous steps helped you resolve the issue, your current installation of Windows may be corrupt. Perform a repair installation and see if it fixes the issue of updates not installing.

• Visit the official Microsoft website to download Windows 11 Installation Media
• Run the Media Creation Tool and select Create Installation Media for another PC
• Select your USB drive
• Let the Process complete of writing the Installation files to the USB drive
• Click Finish
• On the PC you wish to upgrade, Press Windows + E to open the File Explorer

• Open the Removable drive and click Setup.exe
• Accept the license terms on the next screen
• Confirm the Upgrade options – Files, apps and Settings are kept
• Click Install, and the upgrade should start