Can you try gnome-disks utility (Or just "Disks" in the unity dash) to format the drive? If that fails as well, it's a bug in udisks package. If that works fine, than it's a bug in usb-creator.
Interestingly sdb is shown as rotational media in the logs. And usb- creator should be used to erase rotational media. ** Changed in: usb-creator (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1114545 Title: Startup Disk Creator fails when erasing disk To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/usb-creator/+bug/1114545/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs