jojobot

I'm was having this same issue. After installing KB5058499, my VM crashed and BSOD stated Unsupported_Processor. In Unraid, I had to deselect all pinned CPU cores and restart the VM. Once restarting, I noticed the VM was extremely slow. I uninstalled the update and relogged in. I noticed that the VM was still slow, so I edited the Unraid VM settings and pinned CPU cores to the VM. Once I did that, the VM returned to normal operation. Just for giggles, I reinstalled the update, but this time with no CPU cores pinned, and the update completed successfully, but system seemed unstable. Enabled Virtual Machine Platform, repinned CPU cores, and the VM was stable again, with KB5058499 installed. I didn't have any Hyper-V features or Virtual Machine Platform enabled previous to the update and everything was working fine.