Heads up, Windows 11 users! Microsoft has confirmed that the latest security update, known as KB5058405, released during May’s Patch Tuesday, might cause some computers to fail startup. This is a significant issue, preventing users from accessing their operating system on affected devices.
This problem primarily impacts virtual machines used in business and IT environments, so most home users on standard Windows Home or Pro editions should be unaffected. Microsoft is currently investigating and working on a fix.
Windows 11 desktop screenshot
What’s Going On?
After installing the KB5058405 cumulative update, certain Windows 11 systems (specifically versions 22H2 and 23H2) might get stuck on a recovery screen. The error message you see is 0xc0000098, pointing to an issue with a file called ACPI.sys.
Think of ACPI.sys as a critical driver – it’s like the middleman that helps your Windows operating system talk to your computer’s basic hardware regarding power management and how different parts of your computer are set up. If this driver encounters an error, Windows can’t load properly, leading to the boot failure.
Who Is Affected?
Microsoft’s investigation indicates that this issue largely affects devices in enterprise settings. This includes:
- Azure Virtual Machines
- Azure Virtual Desktop
- Virtual machines hosted on-premises using platforms like Citrix or Hyper-V
The company explicitly states that home users running Windows 11 Home or Pro editions on their personal computers are unlikely to encounter this specific problem. This is good news for the majority of Windows users.
What Microsoft Is Doing
Microsoft has acknowledged the issue and is actively investigating the root cause. They’ve added the problem to their Windows release health dashboard, which is where they track known issues affecting updates. More information will be shared as their engineers make progress on finding a solution.
A Recent Trend?
This isn’t the only hiccup Windows users have faced with recent updates. Just this month, Microsoft had to address another known issue that was preventing Windows 11 24H2 feature updates from installing via WSUS after the April security patches.
Earlier instances included emergency updates for Windows 10 to fix BitLocker recovery problems and even an issue where some devices were unintentionally upgraded to Windows 11 despite policies meant to block the upgrade. These situations highlight the complex nature of rolling out updates across a vast ecosystem of devices and configurations. For more context on recent updates, you might be interested in reading about the Microsoft May 2025 Patch Tuesday fixes which addressed numerous security flaws.
The Bottom Line
If you’re using Windows 11 at home, you probably don’t need to worry about this specific boot error. It seems contained to corporate and cloud virtual machine environments. For IT administrators managing these systems, it’s important to be aware of this potential issue following the KB5058405 update. Keep an eye on Microsoft’s official channels for updates on when a fix will be available.
Stay tuned for more tech news and breakdowns. You can explore related topics like Windows Server emergency updates or new features like hotpatching in Windows 11 Enterprise to stay informed on the latest developments from Microsoft.
