Windows Server 2022 update gave ESXi host VMs the blue screen blues

Something likely to be absent from Microsoft's Ignite event is talk of a fix rolled out to deal with malfunctioning Windows Server 2022 Virtual Machines following a problematic update from the company.

The culprit was the KB5031364 October update, which contained a variety of fixes and updates for Windows Server 2022, from changing the spelling of Ukraine's capital from Kiev to Kyiv to addressing issues with the Server Message Block (SMB) service.

However, judging by complaints from administrators, it also broke some important parts of the operating system – notably, starting VMs on VMware ESXi hosts.

According to Microsoft, the issue was dealt with in November's update, KB5032198.

Regarding the original problem, Microsoft said: "After installing this update on virtual machines (VMs) running on VMware ESXi hosts, Windows 2022 might fail to start up. Affected VMs will receive an error with a blue screen and Stop code : PNP DETECTED FATAL ERROR."

The issue affected VMware ESXi hosts. The physical processor needed to be an AMD Epyc, "Expose IOMMU to guest OS" had to be enabled in VMware settings for the VM, and "Enable Virtualization Based Security" and "System Guard Secure Launch" had to be enabled in Windows Server 2022.

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Before the fix, affected administrators – and there were a lot of them – had several workarounds available ranging from toggling settings or deleting specific files to simply uninstalling the patch.

Users expressed disbelief that Microsoft would send an update out into the world that resulted in such carnage. However, anyone who has watched the decline in the quality of the company's output over the years may not be surprised.

After all, it's barely a year since Microsoft broke Hyper-V. In that instance, the issue was so severe that an emergency fix had to be pushed out to give administrators the merriest of Christmases.

Then there was that time earlier this year when Microsoft inadvertently broke VMs running on VMware ESXi hosts. In that instance, a straight uninstall didn't undo the damage; an ESXi upgrade or disabling Secure Boot was needed.

While we applaud the fix turning up in the November release, Microsoft issuing updates that break key functionality should give administrators pause for thought. When it comes to Windows, expect the unexpected. ®