This article explains how to enable a Chromebook to boot from a USB memory drive. This setting can be activated only after enabling the developer mode which involves the initialization of the device, with the consequent deletion of all the data it contains.
Steps
Part 1 of 2: Activate Developer Mode
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Step 1. Back up all data on your Chromebook
Enabling developer mode deletes all files on the Chromebook, including all changes and customizations to device settings.
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Step 2. Turn off the Chromebook
Click on your account profile picture displayed in the main menu and click on the icon Diet.
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Step 3. Press the Esc + F3 key combination while pressing the Power key
The Chromebook will turn on and ask you to insert recovery media.
Some Chromebook models require you to press a reset button with a paper clip or small pointed object while pressing the "Power" button. If your Chromebook has a small hole labeled "Recovery" follow the instructions in this step
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Step 4. Press the key combination Ctrl + D when the screen will appear asking you to connect the rescue media
A confirmation message will be displayed.
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Step 5. Press the Enter key to confirm
The Chromebook will restart. When the conversion is complete, you will see a message similar to the following "Chrome OS verification is disabled" appear on the screen. This warning message will appear every time you turn on your Chromebook.
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Step 6. Press the Ctrl + D key combination when the "Checking Chrome OS" screen is displayed
Your Chromebook's developer mode is now active.
Part 2 of 2: Enable Boot from USB Drive
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Step 1. Press the key combination Ctrl + Alt + F2 from the device Home
The system console similar to the Windows "Command Prompt" will appear.
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Step 2. Type the command sudo crossystem dev_boot_usb = 1 in the window that appears
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Step 3. Press the Enter key
The command entered will be executed.
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Step 4. Connect the USB drive to the Chromebook that it will use for booting
You can now use the system console to reboot the device from the USB memory drive you connected it to.
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Step 5. Press the Ctrl + U key combination when the "Checking Chrome OS" screen is displayed
Your Chromebook will boot up using the USB memory drive you connected it to.