Windows 11 update ->Error while powering on: Failed to start the virtual machine

[paulusHarps]

After a windows 11 update all my virtual machines failed to start, with message:
Error while powering on: Failed to start the virtual machine
First update that caused the problem was around April 7 2023. I solved this by rolling back to previous version of windows, but after a few weeks Windows did an auto update again, and I can no longer roll back to a windows 11 version that works.
Has anyone else seen this? My hardware is AMD Ryzen and VMware Workstation player worked fine before. I even upgraded my VMware player from v 16 to 17, and downloaded a fresh Ubuntu ISO, same problem.

I include log files in the hope it will help someone to figure this out.

Thanks in advance

[Technogeezer · Accepted solution]

You are running a Windows Insider Canary channel build of Windows. There have been many reports of Workstation failing with these releases. Canary channel releases are the least stable of all Insider preview releases and there is no documentation on what they changed. Unless you are a sophisticated developer, why are you using this early and least stable version of Windows?

The VM is failing to start because an error is being thrown by Hyper-V. Perhaps this ought to be flagged to Microsoft as a regression  

I’m sure that VMware’s advice would be to run Workstation on a GA channel release and see if you can reproduce the issue.

You may also wish to see if all Hyper-V components are installed on your VM  Or disable all Hyper-V components (including virtualization based security and memory integrity) so that the VMware hypervisor is used instead of Hyper-V  

[paulusHarps]

Thanks Technogeezer,

I am a developer (not sure how sophisticated) and did sign up for the dev channel of windows 11 for some graphics stuff on wsl 2 about a year ago.

I see in March this year they moved all dev channel people to canary - I did not notice this. I have tried now to switch away from canary channel, but the only option available to me was to switch to dev, and it seems I must wait for the next windows update for anything to change. (unless I do a reinstall of windows, which I am reluctant to do)

I have sent feedback to Microsoft, maybe it will have some effect.

I have checked in windows turn features on and off, and Hyper-V Hypervisor and Hyper-V Services are both off.

BTW, how do you know that it is a Hyper-V problem? I checked the vmware.log file, but did not notice any errors, just some warnings/

Thanks again

Paul Harper

[Technogeezer · Accepted solution]

There is an error in the log about failing to start a vcpu. The monitor mode that Workstation is using (hypervisor in use) in the log is ULM - which indicates Hyper-V (it would be CPL0 if the VMware hypervisor is in use). Since Hyper-V is therefore in charge of running the virtual CPU, it leads to the suspicion that something about it is the culprit if the CPU can’t be started and nothing else has changed.

[Technogeezer]

By the way @paulusHarps I apologize for the tone in my initial reply. It was a bit harsh. We’ve seen a number of reports on Canary channel Windows releases, and I was curious why people were running it. 

[paulusHarps]

No sweat, moenie wurry nie, as they say in Afrikaans

[Technogeezer]

Something I saw in another thread.

VMW 17 + Change vCPU on Win Server 2022 Guest = Gu... - VMware Technology Network VMTN

Wonder if the suggestion in this thread to make a change to the .vmx file might help out?