Microsoft Issues Emergency Windows 11 Update for Installation Failure Loop
Microsoft released an out-of-band Windows 11 update, KB5086672, to fix a widespread installation failure affecting versions 25H2 and 24H2 after the March preview update KB5079391 triggered repeated setup errors. Affected systems entered a loop of failed update attempts and reported error code 0x80073712, which indicates missing or corrupted update files. Microsoft withdrew the faulty preview release and replaced it with a cumulative package that also carries forward March security and quality fixes.
The emergency package moves impacted devices to OS builds 26200.8117 and 26100.8117 and also updates several local AI components. Microsoft said the fix is available through Windows Update, the Microsoft Update Catalog, and manual installation in Settings, while enterprise administrators can accelerate deployment through Intune or Windows Autopatch expedited quality updates. Because the release combines the servicing stack and cumulative update, rollback options are limited and manual removal may require DISM.
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How this story unfolded
4 events from the most recent confirmed update back to the earliest known activity.
Microsoft issues emergency update KB5086672 to fix installation failures
On March 31, 2026, Microsoft released out-of-band update KB5086672 to correct the Windows 11 installation loop problem. The replacement cumulative package included prior March security and quality fixes, advanced systems to builds 26200.8117 and 26100.8117, and updated several local AI components.
Microsoft withdraws problematic preview update KB5079391
Microsoft pulled the March 2026 preview update after identifying that it was causing installation loop issues on Windows 11 24H2 and 25H2 systems. The withdrawal was part of the company's response to stop further impact from the faulty package.
KB5079391 causes Windows 11 installation loop with error 0x80073712
After KB5079391 was released, affected Windows 11 devices began experiencing persistent installation failures and repeated update attempts. Microsoft associated the issue with error code 0x80073712, indicating missing or corrupted update files.
Microsoft releases preview update KB5079391 for Windows 11 24H2 and 25H2
Microsoft issued the March 26, 2026 non-security preview update KB5079391 for Windows 11 versions 24H2 and 25H2. This update later proved to trigger repeated installation failures on affected systems.
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Microsoft Fixes Windows 11 Update Failures Caused by Small EFI Partitions
Microsoft released Windows 11 cumulative update **KB5089573** to permanently fix an installation bug introduced by **KB5089549** that caused some systems running versions **24H2** and **25H2** to fail during reboot. Affected devices typically stalled at about **35–36%** completion, rolled back the update, and returned error `0x800f0922`, with logs indicating insufficient free space in the **EFI System Partition (ESP)**. Microsoft had already applied a Known Issue Rollback and provided a registry-based workaround for enterprise administrators before issuing the permanent fix. The update raises Windows 11 builds to **26100.8524** and **26200.8524**, includes servicing stack and AI component updates, and is available through **Windows Update**, **Microsoft Update Catalog**, **Windows Update for Business**, and **WSUS**. Microsoft said no known issues were identified at release and indicated that the fix will also be included in subsequent cumulative updates, reducing the need for users and administrators to manually resize the ESP or remove security updates.
Jun 2, 2026
Windows 11 KB5089549 Install Bug Blocks Security Updates on Low-ESP Systems
Microsoft confirmed that the mandatory Windows 11 cumulative update **KB5089549** is failing on some devices, leaving them without the latest security fixes. The installation issue is primarily affecting systems with nearly full **EFI System Partitions (ESP)**—especially those with about **10 MB or less** of free space—and commonly triggers errors including `0x800f0922`, `0x80240069`, and `0x80240031`. Affected machines often stall at roughly **35–36%** during restart, then roll back the update instead of completing installation. Microsoft said it deployed a server-side **Known Issue Rollback (KIR)** to mitigate the problem for consumer and unmanaged business devices, with the fix expected to apply automatically after a restart. The company also advised users to reboot and retry the update, while enterprise administrators were told to use a **Group Policy** mitigation for managed environments. Reports also noted that some impacted systems experienced boot issues or degraded performance, adding to broader concerns over recent Windows update reliability problems.
Jun 9, 2026
Windows 11 KB5089549 Install Failures Complicate Microsoft Defender Security Patches
Microsoft confirmed that the Windows 11 security update `KB5089549` can fail to install on systems running versions 24H2 and 25H2 when the EFI System Partition has 10 MB or less of free space. Affected devices typically stop during reboot at about 35–36% completion, return error `0x800f0922`, and roll back the update. Microsoft has issued a **Known Issue Rollback** for consumer and unmanaged business devices, while enterprise administrators must use a Group Policy workaround; for persistent cases, the company also published a registry-based mitigation to reduce reserved EFI servicing padding. The same update also addresses a separate problem that had pushed some Windows 11 devices into BitLocker recovery after earlier 2026 updates. The installation issue is significant because Microsoft’s May security advisories also included multiple **Microsoft Defender** vulnerabilities, with `CVE-2026-41091` and `CVE-2026-45498` added by CISA to the **Known Exploited Vulnerabilities** catalog, signaling active exploitation risk. Additional Defender flaws tracked as `CVE-2026-45584` and related advisories were also published by Microsoft and echoed by national cybersecurity agencies, including Canada’s Cyber Centre and HKCERT, which urged organizations to review the bulletins and apply updates. Microsoft said it is developing a permanent fix for the Windows 11 update failure in a future release.
May 24, 2026