Trying to reset password in Ubuntu 12.04 installed in a Dell Optiplex X386-32 bits. After pressing Shift key during reboot, getting to Recovery and into root editing, I get this (bold font):
guest-KUGyB7@usuario-OptiPlex-GX620:~$ (blinking prompt here at bottom of screen).
It appears that Dell kidnapped Ubuntu's boot sequence. Please, help!!!