Warning: you could wipe any disk!

lsblk # check the name of USB disk: /dev/sdX
time sudo dd if=INPUT.iso of=/dev/sdX bs=8k status=progress oflag=sync

1878384640 bytes (1,9 GB, 1,7 GiB) copied, 263,002 s, 7,1 MB/s 
229888+0 enregistrements lus
229888+0 enregistrements écrits
1883242496 bytes (1,9 GB, 1,8 GiB) copied, 264,033 s, 7,1 MB/s

real    4m24.041s
user    0m0.420s
sys    0m8.736s

Format

gnome-disks

unetbootin

You should format your USB key first

unetbootin

USB Startup Disk Creator

"System > Administration > USB Startup Disk Creator"

usb-creator-gtk

dd

Source: https://askubuntu.com/a/680382

I am aware how old this thread is, but given someone with the same problem pointed me here when asking for advice, I thought I'd share my answer

The answer, alas, is to not use SDC, but the command line.

cd path/to/iso/dir
lsblk
# (identify the flash drive - likely /dev/sdb or /dev/sdc or the likes)
# (you should be able to identify it by its size - or just remove the flash drive, run lsblk again, see what disappears)
sudo dd if=name_of_image.iso of=/dev/sdc # (as appropriate)

This will copy byte-for-byte the ISO to your flash drive, overwriting it completely. It will look like nothing is happening when you run the command, but that's just the 'dd' command - it's not verbose at all. Takes about 1-4 minutes depending on ISO side and write speed of the flash drive.

Note that if this is one of the official Ubuntu respins (Ubuntu, Lubuntu, Kubuntu, etc) then it should be fine to boot from flash disk. Other ISOs may not have compatibility for being written to and booted from a flash disk.

You can convert an ISO to "hybrid" (CD and USB compatibility) by installing the syslinux utility and running isohybrid (which will modify the ISO file itself - maybe do this on a copy of the ISO)

sudo apt install syslinux isohybrid path/to/your.iso Good luck