Hi all!
The latest posts has been about how to get the most of our hardware in a virtual machines. But sometimes you need to revert stuff you do. Or as me, try everything that can go wrong.
When I revert from paravirtulized driver on my Windows 10 vm to NVMe controller everything went fine. But I wanted to try to revert the other way around. But the VM did not boot and got blue screen of death every time (inaccessible boot device.)
But I found a way around this.
The goal for this is to remove the NVMe controller from the boot disk and use any other scsi controller
- We have a VM with NVMe controller working
- Add paravirtulized controller to the vm, so windows can add the driver
- Open a command prompt with an Administrator
- Type in below
bcdedit /set {current} safeboot minimal
5. Shutdown the vm
6. Edit the vm and switch the disk scsi controller to the one you want

7. Start up the machine (it will be in safe mode)
8. After login open a command prompt with admin rights
9. Type in
bcdedit /deletevalue {current} safeboot
10. Restart the vm
11. Done
I hope this help someone out there, because I had a few hours of troubleshooting with this!
Keep hacking!
//Roger