In this howto there are the steps to follow when a Windows 10 OS is not bootable anymore and you haven’t a recovery disk. This is a typical case after a new OS will be installed on Dual boot or boot partition was altered.
- Download Windows 10 iso:
- Download the official Windows 10 image
- Prepare USB to be bootable:
- Open GParted with
- Unplug and plug USB
- Copy all Windows files to the empty USB drive using 7zip with:
7z x -y -o/media/user/path-to-USB/ Win10_1809Oct_Italian_x64.iso
- If something goes wrong during copy, you can mount the ISO image then rsync the source with the USB drive (the trailing slash is important):
cd path/to/usb/drive rsync -avzp /media/myuser/CCCOMA_X64FRE_IT-IT_DV91/ .
- Open GParted selecting the device just written
- Select the new partition then
- Select Partition > Manage flags
- Select boot flag (esp will be auto-selected)
- Use windows tools
- Follow this howto by MS to recover MBR, restore BCD or similar actions
You can follow these steps to write on a USB a recovery ISO from windows the same way.