usb-creator fails to run syslinux due to architecture mismatch

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1446646

From the UsbCreatorLog.txt:

usb-creator 2015-04-21 07:43:35,964 (DEBUG) install.py:232: install_bootloader
usb-creator 2015-04-21 07:43:47,676 (CRITICAL) install.py:99: Failed to install the bootloader.
usb-creator 2015-04-21 07:43:47,678 (ERROR) frontend.py:737: Installation failed.
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/usbcreator/install.py", line 257, in install_bootloader
    timeout=MAX_DBUS_TIMEOUT)
  File "/usr/lib/python3/dist-packages/dbus/proxies.py", line 70, in __call__
    return self._proxy_method(*args, **keywords)
  File "/usr/lib/python3/dist-packages/dbus/proxies.py", line 145, in __call__
    **keywords)
  File "/usr/lib/python3/dist-packages/dbus/connection.py", line 651, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: org.freedesktop.DBus.Python.OSError: Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/dbus/service.py", line 707, in _message_cb
    retval = candidate_method(self, *args, **keywords)
  File "/usr/share/usb-creator/usb-creator-helper", line 226, in InstallBootloader
    popen([syslinux_exe, '-f', device])
  File "/usr/lib/python3/dist-packages/usbcreator/misc.py", line 169, in popen
    startupinfo=startupinfo)
  File "/usr/lib/python3.4/subprocess.py", line 859, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.4/subprocess.py", line 1457, in _execute_child
    raise child_exception_type(errno_num, err_msg)
OSError: [Errno 8] Exec format error

I was unable to recreate this using usb-creator-gtk version 0.2.67. It may be worth noting that udisks --dump works for me and it failed when apport was generating this crash report.

UDisksDump: Error: [Errno 2] No such file or directory: 'udisks'

Actually, it seems that the apport hook calls udisks without checking to see if it is available.

I've fixed the apport hook for usb-creator-gtk in trunk.

Status changed to 'Confirmed' because the bug affects multiple users.

It is possible that this bug is causing usb-creator-gtk to fail today, when a fix for bug #1325801 is released to the trusty-proposed repository and fails to work.

The Vivid version of usb-creator constantly fails to successfully create a Vivid live USB at the point of installing the bootloader.
The USB Key (2 GB) is formatted in FAT32

DistroRelease: Ubuntu 15.04 AMD64
Package: usb-creator-gtk 0.2.67ubuntu0.1
ProcVersionSignature: Ubuntu 3.19.0-16-generic
Architecture: AMD64
CurrentDesktop: GNOME-Flashback:Unity

Same error for me.
Note that this only happens with the 15.04 64 bit image (which I need), but works fine with the 32bit image.
Format 32bit 16g thumb drive as FAT 32.
Fails at install of bootloader.

Right, this explodes because the architecture you're running on doesn't allow starting executables of the architecture you're trying to burn on the USB disk.

Thanks for filing this bug, this is a genuine issue that we had not anticipated in the other bug you linked -- marking Triaged/High.

For now, you may wish to use dd to create these images; for example:
$ dd if=ubuntu-15.04-desktop-amd64.iso of=/dev/sdz bs=512

Will write the image to the USB device directly -- remember to make sure you pick the right device instead of /dev/sdz which should be your USB disk; since dd will happily write the contents of the image where you tell it to without confirmation. If you pick the wrong disk, you can say bye-bye to your data now.

The Precise Pangolin has reached end of life, so this bug will not be fixed for that release