AT LEAST FOR ME FIXED!
The problem I had is that I could not even access to the C : drive and fix the Win10 OS, so what I did and it worked for me it was that:
Steps:
Stop the machine
Do edit virtual machine and select the "virtio drivers ISO" that you can download from https://docs.fedoraproject.org/en-US/quick-docs/creating-windows-virtual-machines-using-virtio-drivers/index.html and save
Start the virtual Windows machine
When the broken windows show you the Troubleshoot, select "Advanced Options"
Now click on "Command Prompt"
Now try to go to C :, D :, E: until doing "dir" you find some directories like "viostor" or "w10" in my case was "viostor"
do (depending on the virtio drivers ISO you have to find the proper folder but allways something related with the name viostor)
cd viostor\w10\amd64
then type:
drvload viostor.inf
Then close the CMD and without restarting click on "Startup Repair" and after getting mad of waiting for 20 mins the windows 10 shines again!!!
Greetings and I hope it will be usefull!!,
David Lyons