Use the Chromebook Recovery Utility

If you need to recover your Chromebook, you can use the Chromebook Recovery Utility to create recovery media and get your Chromebook working like new again.

What you need to create recovery media

Before using the utility, make sure that you have:

• A flash drive or other storage media that can hold at least 4GB and that you don't mind clearing.
• An extra Chromebook, Windows, or Mac computer with administrative rights and Chrome browser installed.

Create recovery media

If your Chromebook isn't working properly, you can use an extra Chromebook or another Windows or Mac computer to create recovery media. Otherwise, you can follow these steps on your Chromebook if you want to create recovery media to use later.

If you're using a Linux computer, follow the instructions listed after Step 6.

Step 1: Install the Chromebook Recovery Utility app

1. Install the Chromebook Recovery Utility app on your Chromebook or on your Windows or Mac computer.
2. Open the app.

Step 2: Identify your Chromebook

1. Type in the model number of the Chromebook you want to recover to get the correct recovery image. You can find that number at the bottom of the error message on your Chromebook or on the recovery screen in the app.
2. Click the Continue button.

Step 3: Insert your USB flash drive or SD card

1. Insert your storage media in to an open USB or SD Card port on your Chromebook or on your Windows or Mac computer. The tool will automatically detect the media.
2. Use the dropdown menu to select the appropriate storage media.
3. Click Continue.

Step 4: Create a recovery image

Important: All of the data on the recovery media will be deleted if you continue.

1. Make sure the media you'd like to use for your recovery is listed.
2. Click the Create now button.

The tool will then create the recovery image on your selected media. Don't remove the flash drive or SD card while this is happening. After you see the message saying that your recovery media is ready, you may remove it from your Chromebook or computer.

Step 5: Recover your Chromebook

Restore your Chromebook using your newly-created media.

Step 6: Erase recovery media (optional)

The Chromebook Recovery Utility partitions the USB or SD media into different sections, which means you can’t store data on it unless you wipe the drive clean.

You can use the Chromebook Recovery Utility to erase the recovery files and partitions so that you can use the USB or SD media for storage again:

1. Open the Chromebook Recovery Utility app and click the settings icon .
2. Select Erase recovery media.
3. From the dropdown menu, select the recovery media you'd like to erase.
4. Click Continue.
5. Make sure the media you used for recovery is listed. Remember, all of the data on the media will be erased.
6. Click Erase now.

The tool will then erase the recovery image on your selected media. Don't remove the flash drive or SD card while this is happening.

After you see the message saying that your recovery media is prepared for formatting, you may remove it from your Chromebook and format it using a tool provided by your operating system.

Create recovery media using a Linux computer

Linux instructions

1. Click here to download the Recovery Tool: https://dl.google.com/dl/edgedl/chromeos/recovery/linux_recovery.sh
2. Change the script permissions to allow execution with the following command: $ sudo chmod 755 linux_recovery.sh
3. Run the script with root privileges with the following command: $ sudo bash linux_recovery.sh
4. Follow the instructions on your screen.

Source : https://support.google.com/chromebook/answer/6002417