"can't unmount /cdrom: Device resource or busy" while installing Ubuntu 12.10 via live USB stick

Question

I am trying to install Ubuntu 12.10 via live USB stick on my Samsung N120 netbook.

I downloaded the ISO and put it on my USB stick with Startup Disk Creator.

When I attempt the install, Ubuntu says:

can't unmount /cdrom: Device resource or busy
Resetting /etc/default/keyboard

(Note that my netbook doesn't have cdrom!) Even if I wait for 15 minutes, nothing moves.

What should I do?

Answer 1

It turned out that I had to reinstall the ISO to the USB flash drive. Then it worked and succeeded in the installation!