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):
'<vm-name>': Attachment '<path to disk>.vhdx' failed to open because of error: 'Incorrect function. ' (7864368). (Virtual machine ID xxxx)
'<vm-name>' Synthetic SCSI Controller (Instance ID xxxx): Failed to Power on with Error 'Incorrect function. ' (0x80070001). (Virtual machine ID xxx)
'<vm-name>' failed to start. (Virtual machine ID xxxx)