I'm trying to make a USB Windows 8.1 bootable from a Windows 8.1 ISO file. My problem is that I don't have any OS on my PC, I just have a live-usb Ubuntu.
And it is the problem, every tutorial, everything I tried requires to install a program (such as grub, unetbootin, mkusb, WinUSB, WieUSB etc…) :
1) Here, it is not the same problem, because he's not in a Live-USB Ubuntu
How can I create a Windows bootable USB stick using Ubuntu?
2) I tried the dd method, but it doesn't work. This guy tried it and has the same problem
How can I create a Windows 10 boot usb from ubuntu?
3) That tutorial is well detailed, but there is a problem, I don't know whether I have to use GTP or DOS partition table, it is unclear and everyone seems not to be sure about what is right
https://onetransistor.blogspot.ch/2014/09/make-bootable-windows-usb-from-ubuntu.html
4) I want a EFI boot because I'm sure that the BIOS could not work with my computer. My ISO take in account the EFI because there is a directory called EFI.
5) I don't have any Windows machine to use Rufus or WIN32.
6) I CAN'T install program, because I'm in a live USB mode, anyway, I've tried to install (for using the programs that must be installed) Ubuntu on my SSD but at the end, it tells me that there is a problem with GRUB (my Ubuntu boot is in EFI mode), and I think that I can't install grub because I'm in a liveUSB…
I think that my only hope is mkusb-nox, which is a command-line tool, but I need to install it too if I have understood?? How can I use it without installing. Is there any solutions to my problem?
I'm sure that I have read everything possible but the problem is really that I can't install in /root a program, because I'm in a LiveUSB mode. I'm really lost and out of solutions.
PS : I've tried the solution consisting in formatting the USB in NTFS, put the "boot" flag and copy (using cp -r /mountpoint/* USBKEY) but it doesn't work, I really don't understand why. Do I need to install Grub on the USBkey? If yes,how can I do it knowing that grub can't be installed because of the live mode.
Sorry for the long message but I try to give everything to you. As you have understood, it is my non-persistent live USB that is really the problem
thanks a lot for your help!
J.
PS : My goal is to install Windows on that computer, not making a dual boot.
PS2 : I use Ubuntu 16.04 live USB
Best Answer
In your question you wrote:
Fortunately things are better than what you thought. It is possible to install a program in a live system, and it can be used.
The installed program will survive as long as the live system is running. If you shutdown or reboot the live system, the installed program will be gone (but can be installed again). In other words, this is a useful option, if you intend to do something once. So it is possible to install mkusb or some other tool and use it to create a USB install drive for Windows 8.1.
There is also an alternative, that should work without installing anything.
See the following link to a 'Do It Yourself' method,
https://help.ubuntu.com/community/Installation/iso2usb/diy
If there are problems with this 'diy' method, mkusb could still work, due to the copying method via a tarball, as described by @MichaelBay in a comment and at this link.