Take the 2-minute tour ×  I have an HP Workstation Z820. I would
like to install Ubuntu 11.04 on it, but I cannot boot the live
CD. There is an SSD and HHD on the machine, but no operating
systems are installed on it. System has UEFI architecture, and
on the BIOS, CD/DVD drive appears under both UEFI Boot Sources
and Legacy Boot Sources.  share|improve this question add
comment  1 Answer  According to HP's Web site, this computer
ships with Windows 8. Therefore, it almost certainly ships with
Secure Boot active. Ubuntu 11.04 was released well before Ubuntu
added Secure Boot support to its OS (with version 12.10), so to
get Ubuntu 11.04's installer to boot, you'll need to disable
Secure Boot. (Note that the procedures to do so vary greatly
from one computer to another; the reference describes how to do
it on one computer, but yours is almost certain to be
different.)  Also, Ubuntu 11.04 is nearly two years old, and it
has some very serious EFI-related bugs, such as this one. What's
more, it's so old that it li