On March 26, Microsoft released optional patch KB5079391 for Windows 11 versions 24H2 and 25H2 – including 29 changes, including improvements to Smart App Control, display and reliability of Windows Hello. According to Windows Latest, the update was not available until download only during one to two hours : Even before a massive deployment, users began to mass report an installation error.
Already the following evening, Microsoft officially suspended the deployment.
«Rollout of this update is temporarily paused due to installation error 0x80073712»
— official statement from Microsoft on support page KB5079391
The code 0x80073712 means that the Windows Component Store (CBS) cannot find or cannot verify the files needed for installation. The system starts the process, cannot complete it – and restores the previous state. In practice, for most, this looks like a “freeze” in an update loop. As Windows Central points out, no PCs crashed – but no users received the update.
Not an isolated bug, but a series
Anyone who has been following Windows 11 for several months knows: KB5079391 is not an exception. According to Windows Latest, in 2025 Windows 11 experienced 20+ major update issuesand 2026 extended this trajectory from the first weeks.
- December 2025: A faulty update left some systems in an “incorrect state.”
- January 2026 (KB5074109): BSODs with code UNMOUNTABLE_BOOT_VOLUME on business PCs – as established by BleepingComputer, due to an earlier incident in December. The extent of the problem has not been revealed by Microsoft.
- February 2026 : A cumulative update caused boot failures on some systems.
- Mars 2026 (KB5079473, Patch Tuesday) : crashes, freezes and application malfunctions — the company released two off-schedule emergency patches in the span of a week, according to TechBuzz.
KB5079391 is already the fifth significant incident in four months. It is telling that this time it is an update preview : This category was supposed to serve as a “safe corridor” for testing before general Patch Tuesday.
Why preview no longer protects
Microsoft’s logic provides for a two-step model: first optional preview updates are published at the end of the month to collect feedback – then, after correction, the changes are integrated into Patch Tuesday. But if a preview is defective to the point of being withdrawn in two hours, the feedback cycle practically cannot take place.
The WebProNews media draws attention to another factor: within the technical community, there is increasing discussion about the impact of downsizing Microsoft’s engineering teams on the quality of quality assurance (QA) – and the company’s ability to maintain a reliable testing process in a context cost optimization.
Microsoft has not yet indicated the cause of the outage, nor a recovery time for KB5079391. If the next April Patch Tuesday goes by without new emergency recalls, it will be the first incident-free month in a long time. Otherwise, the question of the systematicity of problems will cease to be rhetorical.
