Microsoft pulls Windows 11 KB5079391 over 0x80073712 errors, ships KB5086672 fix

On 26 March 2026 Microsoft started offering KB5079391, an optional preview update for Windows 11 24H2 and 25H2, then paused it after devices failed to install it with error 0x80073712. Five days later it shipped an out-of-band replacement, KB5086672. If you look after Windows build agents, developer laptops or golden images, this is a good reminder of why optional preview updates belong in a test ring and not on machines your pipeline depends on.

What happened

KB5079391 was the March 2026 non-security preview (the optional cumulative update Microsoft releases late in the month, ahead of the next Patch Tuesday). It carried 29 changes, including a wider rollout of the Smart App Control toggle, display improvements and better Windows Hello fingerprint reliability on some devices. Windows Latest reported that it was offered on Thursday 26 March and pulled within hours.

Affected PCs showed this Windows Update message: "Some update files are missing or have problems. We'll try to download the update again later. Error code: (0x80073712)." Microsoft's release health notes said the rollout was "temporarily paused due to installation error 0x80073712" and that it had "temporarily limited the availability of this update", so many devices simply stopped being offered it.

On 31 March Microsoft released out-of-band update KB5086672 (OS builds 26100.8117 for 24H2 and 26200.8117 for 25H2). Microsoft says the installation problem "has been addressed in KB5086672". Because it is cumulative, KB5086672 also carries KB5079391's changes plus the March security update KB5079473 and the earlier out-of-band fix KB5085516, which dealt with Microsoft account sign-in failures in apps such as Teams, Edge and OneDrive.

Who is affected

• Windows 11 24H2 and 25H2 devices that tried to install KB5079391 from Windows Update during the short window it was offered.
• Devices with "Get the latest updates as soon as they're available" turned on, which pick up optional previews automatically.
• Not affected: devices that only take Patch Tuesday security updates, and Windows 10. KB5079391 was a non-security preview, so skipping it left no security gap.

What it means for developers and engineering teams

Error 0x80073712 is ERROR_SXS_COMPONENT_STORE_CORRUPT. Windows Update could not find component manifests or payloads it expected in the component store (C:\Windows\WinSxS). Normally that points to a damaged store on one machine. This time it was a packaging problem on Microsoft's side, which is why the fix came as a new update rather than local repair steps. Microsoft has not published a root cause.

For engineering teams the practical lessons are about update hygiene rather than this particular bug:

• Preview updates are optional for a reason. Build agents, self-hosted CI runners and VDI images should take security updates on Patch Tuesday and leave the late-month previews to a pilot group.
• A failed update can break reproducibility. If half your Windows runners have a cumulative update and half don't, flaky test failures can follow OS build numbers. Recording winver/build numbers in CI logs makes that easy to spot.
• Out-of-band fixes arrive fast. Microsoft shipped the replacement in five days. Pausing and waiting is usually better than hand-repairing the component store on many machines.

What to do now

1. Check the build on each machine. Run winver or (Get-ComputerInfo).OsBuildNumber in PowerShell. Builds 26100.8117 / 26200.8117 or later include the fix.
2. Check whether the fix is installed: Get-HotFix -Id KB5086672. If it isn't, install it from Windows Update or the Microsoft Update Catalog. Microsoft says devices need KB5079473 or later first.
3. If a machine still shows 0x80073712 after KB5086672, repair the component store, then retry Windows Update:

   DISM /Online /Cleanup-Image /RestoreHealth
   sfc /scannow

4. Keep optional previews off production fleets. In Intune or Windows Update for Business, put build agents and developer images in a ring that only receives quality updates after a deferral, and use a small pilot ring for previews.
5. Rebuild golden images on a schedule from a known-good monthly cumulative update rather than patching long-lived runners in place.

Related on TechLogHub

• CI/CD: why reproducible build environments matter
• GitHub Actions vs GitLab CI: both support self-hosted Windows runners

Sources

• BleepingComputer: Microsoft pulls Windows KB5079391 update over 0x80073712 install errors (30 March 2026)
• Windows Latest: Microsoft pulls Windows 11 KB5079391 after install error loop (29 March 2026)
• Notebookcheck: KB5086672 out-of-band fix for KB5079391 install failures
• IT-Connect: KB5086672 out-of-band update for Windows 11 (French)