Can a Windows 10 ISO bootable USB be created without third party apps?

Question

I want to create a Windows 10 bootable USB drive (or microSD in USB) through Ubuntu without third party apps.

• I tried dd, but it won't work, no boot.

• I also tried formatting the device as FAT32 and copying the files, but that does not work anymore as one of the files from the ISO is larger than 4 GB.

• The answers on How can I create a Windows bootable USB stick using Ubuntu? all use third party apps or make me copy the files, which won't work anymore.

So how can I create a Windows 10 bootable USB drive through Ubuntu without third party apps?

Answer 1

A simple 'Do it yourself' method

A rather simple 'Do it yourself' method is described at the following links. You can create Windows install drives that work in UEFI mode as well as in BIOS mode,

• help.ubuntu.com/community/Installation/iso2usb

• help.ubuntu.com/community/Installation/iso2usb/diy

• help.ubuntu.com/community/Installation/iso2usb/diy/windows-installer-for-big-files

  This method will work also with [new] versions of Windows 10 and Windows 11, where there is a file, install.wim, with a size > 4 GiB, so that the FAT32 file system cannot manage it, when extracted from the iso file. In this case there will be a small FAT32 partition and a bigger NTFS partition.

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This 'Do it yourself' method is for you

• if you have a Windows iso file that contains a file, install.wim, with a size > 4 GiB, or
• if you don't like PPAs, or
• if you want to 'Do it yourself' and understand the details

Implemented in mkusb version 12.5.6 and newer versions

This 'Do it yourself' method is implemented in mkusb-tow and available via mkusb version 12.5.6 (mkusb-dus) and mkusb-plug.

You get/update this new version of mkusb from the mkusb PPA via the following commands

sudo add-apt-repository universe  # this line only for standard Ubuntu

sudo add-apt-repository ppa:mkusb/ppa
sudo apt-get update
sudo apt-get install mkusb mkusb-plug

sudo apt-get install usb-pack-efi  # only for persistent live drives

• mkusb 12.5.6 - brief description
• mkusb - general description and manual
• mkusb-plug - description and manual

Answer 2

If what you want is to make a bootable Windows USB (for installation purposes) from the Windows OS ISO file, then that could be easier than you think.

1. You will need first to prepare the USB disk by formatting it into MBR/DOS disk format first, which can be done with e.g. gnome-disks by selecting the USB disk then choosing Format Disk... from the main menu like so:

   

2. Choose the right format and click Format... to format the disk:

   

3. Create an NTFS partition on the disk by clicking the + sign and then clicking Next in the top of the dialog box. Then choose For use with Windows (NTFS) and format by clicking Create like so:

   

   Now, your USB is ready.

4. Mount the Windows ISO by right-clicking on it and choosing Open with disk image mounter like so:

   

5. Then select the newly created mount point from the left side of the file manager like so:

   

6. Finally, copy all those Windows files to the NTFS partition you previously created on the USB disk. Wait for the copying process to finish and make sure you gracefully eject the USB disk afterwords to avoid any copy/filesystem errors. That's it.

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Technical Notice

UEFI standards require FAT32 support, but don't require NTFS support nor it prohibits it. However, manufacturers are increasingly adding NTFS support as well lately (I mean in the last decade). Moreover, even before that, most systems ship preconfigured with "UEFI first" firmware setting and not "pure UEFI" mode. Also, systems that can only support "pure UEFI" exist, but are not common.

The assumption that UEFI can only support FAT32/16/12 was never true, please see the 4th paragraph here that sums it up. And as the firmware dedicated chips increase in size, not only NTFS will be supported, but other filesystems will be supported natively as well.