I tried to create a Windows 10 USB boot medium with WoeUSB. I formatted a USB drive with an NTFS partition, but WoeUSB complains with:

Installation failed!
Exit code: 256
Mounting source filesystem...
Error: File "/media/woeusb_source_1543626298_6098/sources/install.wim" in
source image has exceed the FAT32 Filesystem 4GiB Single File Size Limitation
and cannot be installed.  You must specify a different --target-filesystem.
Refer: https://github.com/slacka/WoeUSB/wiki/Limitations#fat32-filesystem-4gib-single-file-size-limitation for more info.
Unmounting and removing "/media/woeusb_source_1543626298_6098"...
You may now safely detach the target device

I've also tried to start WoeUSB via command line, did not work.

sudo woeusb --partition Win10_1809Oct_English_x64.iso /dev/sdb

My iso is located in: home/sawyer/Downloads/Win10_1809Oct_English_x64.iso

Thanks in advance! I've been trying to get windows installed for three nights now, so any help towards that goal is greatly appreciated.


I tested the current woeusb from the PPA (running a persistent live Lubuntu 18.04.1 LTS), and the following command lines work for me.

sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt update
sudo apt install woeusb

sudo woeusb --target-filesystem NTFS --device path/windows.iso /dev/sdx

In my case the iso file was in /media/lubuntu/usbdata/images/ and the target device was /dev/sdb, but in your case check carefully that you will write to the intended drive (avoid destroying valuable data in some other drive),

sudo woeusb --target-filesystem NTFS --device /media/lubuntu/usbdata/images/windows.iso /dev/sdb

Notice that all partitions on the target device must be unmounted.

The created USB boot drive has a small FAT partition (for UEFI boot) and a big NTFS partition with the Windows files. It can install Windows both in BIOS and UEFI mode with woeusb (dated 2018-09-19 (Sept 19 2018) in the PPA).

Using NTFS makes it is possible to use file size > 4 GiB. The size of install.wim is

  • smaller than 4 GiB in some of Microsoft's own iso files, for example in

    • Win10_1809Oct_Swedish_x64.iso

      $ <<<'scale=3;4274234443/2^30' bc
      3.980                              # < 4 GiB
  • greater than 4 GiB for some iso files for particular computers, OEM, but also in several of Microsoft's own iso files, for example

    • Win10_1809Oct_English_x64.iso

      $ <<<'scale=3;4396229344/2^30' bc
      4.094                              # > 4 GiB
    • Win10_1809Oct_EnglishInternational_x64.iso

      $ <<<'scale=3;4386496792/2^30' bc
    • Win10_1809Oct_German_x64.iso

      $ <<<'scale=3;4401709065/2^30' bc
    • Win10_1809Oct_Spanish_x64.iso

      $ <<<'scale=3;4404104344/2^30' bc

There is also a GUI version woeusbgui. I don't think is has the option to create a target drive with a FAT file system for UEFI plus an NTFS filesystem, so I would recommend using the command line version woeusb.

Edit: You can do it yourself with detailed help at


This method works in both BIOS and UEFI mode and also with secure boot. (But in most cases it should be possible to turn off secure boot, use the drive created by woeusb, and turn on secure boot again.)

  • This answer also worked for me. For those who are unsure how to unmount, I did this in the command line. Use lsblk to determine where your USB device is. In my case it was sdd1, and I did sudo umount /dev/sdd1. After, I used the command above to create the USB. Note that I had to remove the 1 from the drive, so at the very end of the woeusb command, I used /dev/sdd. – rayryeng - Reinstate Monica Jan 7 at 22:34
  • I guess it's just the GUI. I formatted my USB to NTFS and followed instructions with GUI and get this error every time. Using the command line with flags is the only way to get this to work in Ubuntu 18.04 with the current PPA. Seems like the GUI only knows how to format to FAT, and ignores that the partition is already formatted to NTFS. – Routhinator Jan 19 at 22:22

Couldn't reproduce the error as running that command produced a different error (check_runtime_parameters: Error: Target media "/dev/sdb" is not an partition!).

What seemed to work was to wipe and build a boot drive from scratch with:

sudo woeusb --tgt-fs NTFS -d ~/Downloads/Win10_1809Oct_English_x64.iso /dev/sdb


Some third-party installers, like your Win10_1809Oct_English_x64.iso, feature Windows installation images greater than 4GB making FAT32 as target filesystem impossible. NTFS filesystem support has been added to WoeUSB 3.0.0 and later. If your version of WoeUSB is earlier than 3.0 please update it. The latest version of WinUSB at time of posting this answer is 3.2.10.

For WoeUSB v3.0 and later the --format command-line option is no longer available.

Try opening woeusbgui from the terminal with the following command:

sudo -H woeusbgui &>/dev/null
  • 2
    My USB is 8GB. My interpretation of the warning was that FAT32 formatted USB's can not handle files larger than 4GB, so it's necessary to format in NTFS. Thing is, I have formatted my USB in NTFS, but it's like WoeUSB can't see that. – SLD Dec 1 '18 at 1:27

Out of some unknown reason, the above things solutions https://askubuntu.com/a/1098185/846139 or https://askubuntu.com/a/1098076/846139 did not work for me as expected.

There seems to be a problem with the argument parsing in woeusb v3.2.12.

Putting that target filsystem option at the beginning did not work in self-built WoeUSB v3.2.12 on ubuntu 18.10 cosmic.

What did work, however:

sudo woeusb -d  /somewhere/Win10_abcd_xy_x64.iso /dev/sdb --target-filesystem ntfs
  • Interesting :-) woeusb works well for me in Ubuntu 18.04.1 LTS, and the same version of woeusb seems to be ported to the PPA for 18.10. Did you try your command line with --target-filesystem ntfs at the end also with the version from the PPA? – sudodus Mar 17 at 10:36
  • the ppa version does funny things: $ woeusb --version @@WOEUSB_VERSION@@ – qbit Mar 18 at 19:45
  • 1
    and yes, the ppa version WoeUSB v@@WOEUSB_VERSION@@ (3.2.12-1~webupd8~cosmic0) also accepts the appended --target-filesystem option but NOT when given as second option sudo woeusb -d --target-filesystem ntfs ... – qbit Mar 18 at 19:55

protected by Thomas Ward Feb 3 at 2:52

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.