How to install Ubuntu from USB

Question

I have Windows 8.1 and Ubuntu 12.04 (Precise Pangolin). I want to install Ubuntu 14.04 (Trusty Tahr) on 12.04.

I downloaded the .iso file and UNetbootin. I made a bootable USB using UNetbootin.

I want to install Ubuntu, but the pc doesn't start the USB. Boot options priorities have only Windows and Ubuntu, not CD-ROM or USB.

How can I start pc on USB? How can I install Ubuntu from a bootable USB?

Also, I set a disabled value for "Secure Boot Control".

Update: I use a different USB device. I can start from USB and install Ubuntu.

Answer 1

It seems that you are using UEFI (otherwise Secure Boot should not be an option).

Some - if not all - motherboards do not display boot options as long as the device is not inserted.

But first, make sure you are using a recent Ubuntu 64bit version. Also, if on the device (when you open it) there is an EFI directory it should be able to boot via UEFI. Some motherboards though provide compatibility options to also boot non-UEFI-ready ("Legacy") operating systems which might stop it from booting an UEFI bootable. Make sure you deactivate those settings but be warned: USB-Keyboards might not work then before booting an OS - so you cannot go into the UEFI Setup via pressing a button but need tom, for example, use Windows8.1's advanced reboot. After this is all correct, try inserting the USB, go into UEFI and select it as first boot device.

Answer 2

As you are using Windows, you might need this:

Create a bootable USB stick on Windows

Most current BIOSes have a key to boot from alternative devices, so you might need not change the boot order. This guide says the key F12:

Install Ubuntu desktop

Answer 3

Ubuntu has a built-in application for creating a bootable Ubuntu live USB for installing Ubuntu called Startup Disk Creator which is more reliable than UNetbootin. Search the Dash for Startup Disk Creator and click the Startup Disk Creator icon to open the Make Startup Disk window.

The USB flash drive that you use with Startup Disk Creator should be 2GB or larger. For Ubuntu 18.04 and later it should be 4GB or larger. Startup Disk Creator will automatically format your USB flash drive to FAT32 and make it bootable. If you have only one USB flash drive plugged in to your computer, Startup Disk Creator will select it automatically. Be very careful to select the USB flash drive in the Make Startup Disk window in order to avoid overwriting the partition which Ubuntu is installed on, which may make Ubuntu unbootable. In the screenshot below you can see how the USB flash drive Device is identified by its model name, the same model name that appears under the Drive heading after Model: in the Disks (disk utility) application.

^{Startup Disk Creator in Ubuntu 16.04}

You can also move the Stored in reserved extra space slider back and forth to create some reserved extra space for persistent file storage across reboots. In Ubuntu 16.04 and later Startup Disk Creator no longer has the persistent file storage option. Persistent file storage might be coming back in Startup Disk Creator in 20.04. It's already back in 19.10 in UNetbootin and Rufus. For best results please upgrade Rufus to version 3.9 or later.

In order to enable your computer to boot from the USB flash drive, you must enter your BIOS/UEFI setup utility by pressing one of these keys, usually: Delete, F2 or F10 as soon as the motherboard / computer manufacturer logo splash screen appears when the computer is booting. In the BIOS/UEFI menu, you need to change the boot order so that the USB flash drive, which is usually called USB-HDD in newer computers, is the first entry in the boot sequence, and then save your new settings and exit the setup utility.