Virtual machines failed to start after installing Oct 2023 Update (KB5031364)

Martin Vogt 71 Reputation points

Hi all

After installing the Oct patch on Windows Server 2022 Standard 21H2, most of the virtual machines don't start anymore. There is a known issue described in the KB below, but it's not true only VMs which secure boot are affected.

Uninstalling the update fixes the problem and the VMs are starting up normally. Anyone have a fix for this?? I cannot beleve that MS is rolling out an update like this > This will hit a lot of admins quiet hard!

After installing this update on guest virtual machines (VMs) running Windows Server 2022 on some versions of VMware ESXi, Windows Server 2022 might not start up. Only Windows Server 2022 VMs with Secure Boot enabled are affected by this issue. Affected versions of VMware ESXi are versions vSphere ESXi 7.0.x and below.

The errors i receive when i want to power the machine (from the Hyper-V worker event log):

EventID 12140
'<vm-name>': Attachment '<path to disk>.vhdx' failed to open because of error: 'Incorrect function. ' (7864368). (Virtual machine ID xxxx)

EventID 12010
'<vm-name>' Synthetic SCSI Controller (Instance ID xxxx): Failed to Power on with Error 'Incorrect function. ' (0x80070001). (Virtual machine ID xxx)

EventID 12030
'<vm-name>' failed to start. (Virtual machine ID xxxx)
Windows Server
Windows Server
A family of Microsoft server operating systems that support enterprise-level management, data storage, applications, and communications.
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A Windows technology providing a hypervisor-based virtualization solution enabling customers to consolidate workloads onto a single server.
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Accepted answer
  1. Chris Wroten 145 Reputation points

    For me, on an impacted VM, I was able to resolve this by deleting some extra files used when running the VHDX. Specifically, there was an .mrt (Modifiable Region Table) file and a .rct (Resilient Change Tracking) file for the VHD still present after shutdown/save/patch update and these were the cause behind the system being unwilling to start the VM. Deleted them, and it started right up. Probably lost information regarding the delta from the last backup time, as that seems to be what these files are used for, but it's better than rolling back an update or having an unusable VM.

    14 people found this answer helpful.

14 additional answers

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  1. Paul Coleman 20 Reputation points

    Got my HyperV 2019 Server working again.

    uninstalled KB5031222 which also removed 5031361. Rebooted, and They did not autostart, but I can now start them again.

    wusa /uninstall /kb:5031222

    2 people found this answer helpful.
    0 comments No comments

  2. Martin Vogt 71 Reputation points

    I opened a support ticket at Microsoft. Can't beleve they released this update though the knew that it will cause problems on Hyper-V machines.

    Interesting fact: Not all VM are affected, but i couldn't figure out the difference between the affected/not affected ones. For the affected VMs, i'm event unable to mount the .vhdx disks. Also Linux machines are affected regardless of secure boot turned on or not.

    2 people found this answer helpful.
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  3. Jetze Mellema 11 Reputation points

    Was able to resolve this on Server 2022 by uninstalling KB5031364.

    wusa /uninstall /kb:5031364

    2 people found this answer helpful.
    0 comments No comments

  4. Jake Camp 11 Reputation points

    Removing the SATA controller from the VM did the trick for me

    2 people found this answer helpful.