Cannot update windows 11 to 24H2 - CPU not supported

I just installed Windows 11 from a Win11 24H2 iso image. Everything went fine until Windows Update installed "2025-06 Cumulative Update for Windows 11 Version 24H2 for x64-based Systems (KB5063060)". After restart I got the blue screen with a message indicating "Unsupported CPU". After a couple of (auto)restarts, Windows rolled back and booted again without trouble and now clicking on search for updates (on Windows Update) does not shows KB5063060 (which apears on updates history as "not able to install 0x800f0845").

My virtual machine was set to "host" for CPU emulation since the beguining and virtio 0.1.271 (which seems to be the latest version) was installed before upgrades. Host CPU is AMD Ryzen 5 5600X.

KB5063060 seems to upgrade the system to OS Build 26100.4351. After roll back, Windows shows OS Build 26100.1742. I gues something on OS Build 26100.4351 triggers the unsupported CPU BSOD.
 
Last edited:
Adding args: -cpu 'host,arch_capabilities=off' to config file of virtual machine (under /etc/pve/qemu-server/) indeed solved the problem. I had to download KB5063060 from Windows Catalog manually to reinstall it. After reboot, Windows shows OS Build 26100.4351 and KB5063060 is listed on update history as succefully installed.

Thank you for the reference @_gabriel :)
 
Perhaps useful for someone, I have an AMD 2990wx as host machine, it seemed to choke on KB5058499 about a month ago. It would reboot automatically and go into recovery mode. I couldn't find much info about it but setting the CPU Type to x86-64-v3 made it work again. Microsoft removed the support for these CPU's several years ago but it seems they just started to enforce it recently.
https://learn.microsoft.com/en-us/answers/questions/1165578/windows-11-supported-cpu-list-changes