Booting a computer from a USB Key
Firstly, the ability to access a systems UEFI/BIOS or it’s boot menu very much depends on the type of computer, its age and the security features which have or have not been implemented.
Effectively, there are two ways in which you can boot a computer from a functioning USB key or flash drive.
- Using the Boot Menu to select USB as the option to boot from (Recommend).
- Modifying the systems BIOS/UEFI. To set the USB drive as the first boot device.
And if necessary, returning the settings to their original state, when done.
Method 1: Using the Boot Menu
- Make sure the laptop or computer is switched off and not sleeping or in hibernation.
- Insert the bootable USB flash drive into the device.
- Power on the computer
- When vendor logo appears on screen, press the Boot Key repeatedly until the menu appears.
(A table containing BIOS and Boot Key options for various systems is set out below).
- When Boot Menu appears, choose USB Disk or UEFI: USB Disk to boot your computer.
Note: Some systems identify this as USB HDD or something similar.
Method 2: Set USB drive as first boot device in BIOS/UEFI
Details of how to achieve this are set out below for completeness.
However, if you are seeking to obtain a bit-by-bit image from a system and you are a novice, we would not recommend this method and would suggest you seek advice before proceeding. This is especially so if the target device was pre-installed with any Windows OS from 8 onwards as your actions will entail making a number of modifications to a system which will need to be both justified and recorded.
For new computers pre-installed with Windows 8 onwards:
Start computer and press UEFI key to enter UEFI BIOS Utility window.
- Click Exit/Advanced button in the upper right side of window.
- Choose Advanced Mode.
- Choose Boot in sub-menu.
- Navigate to the First Boot Device using the PgUp and PgDown buttons, when selected press Enter.
- Select USB flash drive from the pop-up dialog and press Enter, it will then be shown as the first boot device.
- Press F10 to save changes and exit.
From this point on, every time the system starts it will first look for a bootable USB key
For older computers with traditional BIOS or systems running Linux operating system.
- Make sure the machine is switched off
- Power on the computer, press BIOS Key to enter BIOS Setup Utility.
- Enter Boot option tab and go to Boot Priority or boot device priority.
- Select USB drive or USB HDD as the first boot device.
- Press F10 to save the BIOS setting and exit.
- Insert USB flash drive into the computer.
- Restart the computer
- The system will look to boot from the USB Key.
As with other devices accessing MacBooks depends to a large degree on what security features are available and have been implemented. To find out whether it is possible to boot your MacBook from a USB simply
- Plug the key into an available port on the Mac.
- Power on the system.
- Press and hold the Option (Alt) key on the keyboard when the computer starts.
Select the USB drive as the start-up disk when the option appears.
(The USB key option will be orange in colour).
UEFI/BIOS & Boot Menu Keys
|Computer Brand||Type||Boot Menu Key||BIOS/UEFI|
|Acer||generic||F12, F9 or Esc||Del, F2|
|HP||generic||Esc, F9||F10, F1, Esc|
|HP||desktop||Esc, F9||F10, Esc|
|Lenovo||desktop||F8, F10, F12||F1, F2|
|Sony||F10, F11, Esc, Assist Button||F1, F2, F3, Assist Button|
|Toshiba||laptop||F12||F1, F2, F12, Esc|