Failed to install Natty on a USB key

[delance]

Binary package hint: ubiquity

I downloaded Natty daily build the 15 February.
Using System->Administration->Make a startup disk, I succeeded to make a bootable USB key.
After I tried to install Natty on another USB key (to check further check hardware compatibility on my PC).
At 99% if failed.
Tried installation a second time, and failed again.
Despite this I tried to boot on this second key, and it failed to boot.

Don't convert this bug into a question as I'm the guy who answers such question in Launchpad Answers.

[Jean-Baptiste Lallement (jibel)]

Thanks for your report.

I affecting to usb-creator since the bug is with the creation of the key not the installer.

[Michal Suchanek (hramrach)]

Guess this makes usb-creator useless in Ubuntu and Ubuntu uninstallable from USB.

I guess this is quite important issue.

[Michal Suchanek (hramrach)]

With Natty release in kvm with usb flash attached:

 - with usb flash containing an iso image (copied with dd) usb-creator-gtk offers only the option to erase the flash and fails to do so, gparted fails to repartition
 - repartitioning with cfdisk creates a partition table that gparted understands. Created a single fat32 partition over the whole device. usb-creator-gtk offers only the option to erase device which again fails.
 - created a fat32 filesystem over the whole device (superfloppy) usb-creator-gtk offers only the option to erase disk which fails

The error gparted reports in terminal:

Input/output error during write on /dev/sda
Error fsyncing/closing /dev/sda: Input/output error

As the only error in GUI is reported when creating the partition table I guess this is the cause.

Interestingly, the partition table is created. cfdisk does not have this issue while creating a partition table.

Another interesting thing is that rebooting with the flash disk already partitioned and formatted fixes the issue.
usb-creator-gtk offers the option to make a startup disk then.