KB5009586 & KB5009624 Breaking Hyper-V

New Contributor

KB5009586 & KB5009624 on my 2012 and 2012 R2 Hyper-V Servers is causing my VMs to not start at all. Hyper-V cannot start any of my VMs until the KBs are uninstalled. This update needs to be pulled as it's breaking Hyper-V on 2012 and 2012 R2 servers.

39 Replies
I agree lets pull this update
I confirm that after updating kb5009586, Hyper-V was disconnected, I wrote that virtualization is not enabled in the BIOS. After removing the update, everything worked. Windows server 2012
Merci, j'avais le même problème.
J'ai désinstallé la KB5009624 et les vms ont pu démarrés
The same i confirm KB5009624 on 2012R2 HyperV can't launch VM (Error Hypervisor not started) , once uninstall KB5009624 all VM start again ... 1 hours lost to find it grrrrr ;)
Same here, Hyper-V stuffed. Also can't uninstall KB5009624. Joy.
The same thing happened to me on Windows 2012. After removing the KB5009624 update, the problem was normalized.
Same here, took a couple hours to figure out but once I removed this update I was able to start my VM's.

Same problem here. Since this update my VMs do not boot, with error stating that hipervisor is not running. After I delete the update, all returns to normalcy.

From Brazil. The same problem, I confirm KB5009624 on 2012R2 HyperV can't launch VM (Error Hypervisor not started) , once uninstall KB5009624 all VM start again

The same here, I had to uninstall this update and restart the server, then hyper-v worked fine @aku017 

@aku017 Same problem and it keeps trying to reinstall. This has effected at least 6 host servers. Something needs done.



I can confirm;


2022-01-Security Monthly Quality Rollup for Windows Server 2012 R2 for x64-based systems (KB5009624) 547.5MB 


installed by windows updates, then after host (W2012 R2 std DELL R720) reboots (if the virtual's are powered on or off), once rebooted the virtuals are in "saved" state, even after deleting save state in hyperv manager the virtuals will not run until the Windows update is removed and host rebooted.  



100% happened to us here
Dell R620 (yes it is old - stop laughing at us)
- double checked in bios CPU was set for virtualization
- double checked in bios DEP was turned on
Hypervisor was running, yes that vmms service was running, stopped it + started it, to no avail.
uninstalled the win update
Thanks man!

+1 same issue on Windows Server 2012 R2 with HyperV - Unable to start guest machines

@aku017 same here

Thanks for the info. You saved my bacon today.
Just in case: Hyper-V failed after KB5009624 both in a R620 and X3550M3 but our trusty HP DL380G6 keeps working even with the patch applied.
I confirm too, the same problem.
Same! Why is this update still being published? It needs to be pulled until fixed.
that's interesting, so the Dell failed but the HP DL ProLiant worked? so it could be to do with the way the hardware BIOS gives CPU hypervisor info to the operating system on Dell's?