KB5123099 (Server 2016 Sept 2026 LCU) fails with 0x8007065E and MSU cannot be opened by 7-Zip

Sammy Mah 35 Reputation points
2026-09-09T05:12:23.62+00:00

I downloaded https://catalog.s.download.windowsupdate.com/c/msdownload/update/software/secu/2026/09/windows10.0-kb5123099-x64_28560cfadc1030ab60e40ddacd3683165f40bc58.msu

and the file is corrupt. I cannot extract using DISM or 7zip. I also downloaded on different computers, internet connection locations.

OS: Windows Server 2016 Essentials

Version: 1607

Build before update: 14393.9418

Successfully installed:

KB5122874 (SSU)

Failed:

KB5123099 (LCU)

Error:

0x8007065E

Data of this type is not supported.

Troubleshooting performed:

  • Rebooted after SSU installation
  • No RebootPending registry key
  • DISM /ScanHealth = No component store corruption detected
  • DISM /CheckHealth = No component store corruption detected
  • Update not already installed
  • Re-downloaded package on different computers.
  • MSU cannot be opened/extracted with 7-Zip
  • Other admins report similar behavior on Reddit /r/sysadmin - Search KB5123099 (as of Sept. 08,2026)
  • PS C:\temp\2026.09> Get-FileHash "C:\temp\2026.09\windows10.0-kb5123099-x64.msu" -algorithm SHA1

Algorithm Hash Path


SHA1 745EB9039F8A8CB857090CE23EADBB06BFC92C3D C:\temp\2026.09\windows10.0-kb5123099-x64.msu

and my SHA1 is different from the published SHA1: windows10.0-kb5123099-x64_28560cfadc1030ab60e40ddacd3683165f40bc58.msu (SHA1: KFYM+twQMKtg5A3azTaDFl9AvFg=)

here is my SHA256:

 E4A9D660F56139EC89496CF68E710C2CC52293EB335A9DD6E74563F20650B6AF

Can someone help fix this .msu?

Windows for business | Windows Server | Devices and deployment | Install Windows updates, features, or roles
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Answer accepted by question author
Hoang Le 4,665 Reputation points Independent Advisor
2026-09-09T05:51:38.86+00:00

Hello Sammy Mah,

The error you are hitting with KB5123099 is not a local corruption but an issue with the package itself. The SHA1 and SHA256 you calculated do not match the published catalog hash, which means the file on the update servers is invalid. That explains why 7‑Zip and DISM cannot open it and why Windows Update returns 0x8007065E (“data of this type is not supported”). Since you already confirmed the SSU KB5122874 is installed and the component store is healthy, there is nothing further you can fix locally. The only resolution is to wait for Microsoft to re‑publish a corrected .msu for KB5123099, or alternatively install the cumulative update once it is re‑released through Windows Update. At this point, do not attempt manual extraction or forced installation, as the package is genuinely broken upstream.

If my answer is useful for you, please hit Accept the answer to support me.

Thank you,

HL.

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  1. Sammy Mah 35 Reputation points
    2026-09-10T04:33:37.8866667+00:00

    They must have fixed it today, 2026.09.09 cause i was able to download using PS and Chrome/Edge from here: https://catalog.update.microsoft.com/Search.aspx?q=KB5123099

    I was able to open both downloaded .msu with 7zip.

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