Latest Patch Tuesday Update Causing Boot Failures on Windows 11 VMs

Microsoft’s latest Patch Tuesday update is causing major headaches for IT admins, especially those managing virtual environments, by failing to install and forcing Windows 11 systems into recovery mode with critical errors. Microsoft has confirmed the issue with this update and is urging admins to delay installation until a fix is released.

According to Microsoft, multiple users have reported that the KB5058405 update, released on May 13, fails to install on certain Windows 11 devices, primarily virtual machines such as Azure Virtual Machines, Azure Virtual Desktop, and on-premises VMs hosted on Citrix or Hyper-V. When the installation fails, the system enters recovery mode and displays the following error message:

“Your PC/Device needs to be repaired. The operating system couldn’t be loaded because a required file is missing or contains errors. File: ACPI.sys. Error code: 0xc0000098,” Microsoft explained.

This error is related to the ACPI.sys file, a core Windows system driver that helps the operating system manage power functions like sleep, hibernation, and battery usage. It acts as a bridge between Windows and the system firmware in order to ensure smooth control of hardware resources and system events. After the update attempt, this file appears to be either corrupted or missing, which prevents the system from booting properly.

Which Windows 11 systems are affected by the update failure?

Microsoft notes that this issue primarily affects enterprise customers running virtualized environments. However, Windows 11 Home and Pro users on physical machines are unlikely to be affected by this problem.

Additionally, Microsoft has mentioned that other system files may also trigger the same recovery mode error. Some users are seeing a different error code (0x8007007e), which usually points to a missing or corrupted system file. This suggests the latest update might be causing wider file integrity issues that could impact different system components, depending on the device or environment.

What IT Admins should do until the fix is released?

Microsoft says that its engineers are currently working on a fix and plans to release an out-of-band update in the coming days. In the meantime, the only recommendation is to avoid installing the update until a solution is available.

However, Microsoft Azure customers who have already installed the problematic Windows 11 update are advised to fix their virtual machines (VMs) by following the instructions available on this support page.