security update fails to install

Question

Security update fails to install: 2026-03 Security Update (KB5079473) (26200.8037) How do I get this to work?

Answer 1

I'm still experiencing install errors. Tried manual installs, turning virus off, sfc scanning. Nothing works.

Answer 2

Please try installing this specific update manually from update catalog:

https://www.catalog.update.microsoft.com/Search.aspx?q=KB5079473

Let us know if this helps!

Answer 3

Hi,

1. What troubleshooting steps have you tried so far to avoid repeating them?
2. In your search bar, type winver and press Enter. Please send a screenshot of the result.

Answer 4

KB5079473 is a cumulative update for Windows 11 24H2/25H2. If it repeatedly fails to install, use the following steps to get it installed manually.

1. Confirm Windows 11 version and architecture
   • Go to Settings → System → About.
   • Confirm that the Edition is Windows 11 version 24H2 or 25H2 (KB5079473 applies only to these).
   • Note the System type: x64 or Arm64.
2. Try installing via Windows Update again
   • Go to Settings → Windows Update.
   • Select Check for updates and let Windows try to install KB5079473.
   • If it still fails, proceed with manual installation.
3. Manually install KB5079473 from Microsoft Update Catalog
   1. Open the Microsoft Update Catalog.
   2. Download the package that matches the system architecture:
      • x64: Windows11.0-KB5079473-x64.msu
      • Arm64: Windows11.0-KB5079473-arm64.msu
   3. Option A – Install directly (simplest):
      • Double‑click the downloaded .msu file and follow the prompts; or
      • Use Windows Update Standalone Installer as described in Description of the Windows Update Standalone Installer in Windows.
4. If direct install still fails, use DISM / Add-WindowsPackage First, create a folder and move the MSU file there, for example C:\packages.
   • For x64 PCs (running Windows):
     • Open Command Prompt as administrator and run:

              DISM /Online /Add-Package /PackagePath:C:\packages\Windows11.0-KB5079473-x64.msu
       

     • Or open Windows PowerShell (Admin) and run:

              Add-WindowsPackage -Online -PackagePath "C:\packages\Windows11.0-KB5079473-x64.msu"
       

   • For Arm64 PCs (running Windows):
     • Open Command Prompt as administrator and run:

              DISM /Online /Add-Package /PackagePath:C:\packages\Windows11.0-KB5079473-arm64.msu
       

     • Or open Windows PowerShell (Admin) and run:

              Add-WindowsPackage -Online -PackagePath "C:\packages\Windows11.0-KB5079473-arm64.msu"
       

   DISM will automatically detect and install any prerequisite MSU files for this KB if they are in the same folder.
5. If DISM reports missing prerequisites KB5079473 can also be installed by applying its MSU files in order:
   • For x64:
     1. windows11.0-kb5043080-x64_953449672073f8fb99badb4cc6d5d7849b9c83e8.msu
     2. windows11.0-kb5079473-x64_651d0cdb7665e03bb80b4c198784b255081032d2.msu
   • For Arm64:
     1. windows11.0-kb5043080-arm64_df540a05f9b118e339c5520f4090bb5d450f090b.msu
     2. windows11.0-kb5079473-arm64_629cb153c8cb6b7257375994cfcf1b934a0cdafd.msu
   Install each file individually in that order using either:
   • DISM (DISM /Online /Add-Package /PackagePath:<path-to-msu>), or
   • Windows Update Standalone Installer (double‑click each .msu).
6. Servicing stack considerations KB5079473 includes the latest servicing stack update (SSU) for Windows 11 (KB5083532 – 26100.8035). No separate SSU installation is required; installing KB5079473 via Windows Update or Catalog will also update the servicing stack.
7. If installation still fails and the system is unstable Community reports indicate that in some cases where KB5079473 repeatedly fails and causes broader issues (e.g., app corruption), an in‑place reinstall of Windows 11 using current media and then re‑running Windows Update has resolved the problem. For a guided path, see the official article on how to fix issues by reinstalling the current version of Windows: https://support.microsoft.com/en-us/windows/fix-issues-by-reinstalling-the-current-version-of-windows-497ac6da-7cac-4641-82a5-f50398d879a0 After reinstalling, run Settings → Windows Update → Check for updates and allow KB5079473 to install normally.

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References:

• March 10, 2026—KB5079473 (OS Builds 26200.8037 and 26100.8037)
• March 10, 2026—KB5079473 (OS Builds 26200.8037 and 26100.8037)#x64-instructions
• March 10, 2026—KB5079473 (OS Builds 26200.8037 and 26100.8037)#Arm64 instructions
• March 10, 2026—KB5079473 (OS Builds 26200.8037 and 26100.8037)#Windows 11 servicing stack update (KB5083532)- 26100.8035
• Latest Security Update KB5079473 (26200.8037) Fails to Install - Microsoft Q&A
• KB5079473 fail with 0x80073712 while inplace upgrade fail with 0x8007042B - Microsoft Q&A