A borrowed a friend workstation with Windows 7 and Ubuntu 10.10. I do not have the administrator password and I would like to format everything and install Ubuntu 12.04. I have put the iso on the usb using PendriveLinux and restarted the machine. At the boot I am presented with several options but those Ubuntu ones simply load my friends Ubuntu 10.10 OS (for which I have no password). edit: I fixed this by pressing F12 at the boot before it gave me that prompt (called GRUB). I clicked USB and finally install.