How to Boot from a USB device

It is possible to boot your computer from a detachable USB device. You might want to do this if your computer has a virus or your installed operating system is not booting. You have to install an operating system onto your USB first. When you boot from the USB your computer will run that operating system instead of your operating system installed on your computer. You can use a USB stick or external hard drive, either one works. It’s simple to do and won’t take longer than 15 minutes. The steps below show you how to boot from a USB device.


  • In the computers BIOS there is a list of options where you can decide where you want the computer to boot from first. Your hard drive should be first on that list but we want to change that to the USB device so that the computer boots from our USB. Remember that once set like this your computer will look for the USB device when booting in the future so you may have to change the settings back if you experience any problems.
  • Once you have the BIOS boot list ready you can plug in your USB device and restart your computer.
  • When your computer restarts and turns on you may see a message that asks you to press any key to boot from an external device. If you do nothing then the computer will probably boot from the next device in the BIOS list. This may be your hard drive for example. However your computer may not show this message and immediately boot from the external USB device.
  • After this you should see your computer load to the operating system (for example, Windows 8 or Linux) you have on your USB device.


If you find that your USB doesn't boot then then make sure that your BIOS settings are correct. Also make sure that no other USB devices are connected to the computer. You could change the USB port that it is connected to. Lastly recopy the operating system again to the USB device in case it had been installed with errors.

Computing | Systems

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