Downgrade Your Nexus Devices Back to Android 5.1.1 Lollipop

In this guide, we show you how to downgrade your Nexus devices back to Android 5.1.1 Lollipop. Recently, Google updated their Nexus range of devices, such as Nexus 5, Nexus 6, Nexus 7 and Nexus 9 to Android 6.0 Marshmallow, but if your prefer Android Lollipop afore the Marshmallow, this guide is for you.

Downgrading firmware on a Nexus device is rather a simple process, but it requires knowledge on flashing firmware manually on Android devices. If you do not want Android 6.0 Marshmallow and wish to downgrade your Nexus device back to Lollipop, read on to know how it is.

About Android 6.0 Marshmallow: This update brings various software fixes, new features and security enhancements to Nexus devices. You should feel faster performance, get a prolonged battery life, and enjoy new features like Now on Tap, personalized app permission, Doze mode, System UI tuner, simple volume control, new gestures and more, once you updated your device to Android 6.0.

How to Downgrade Nexus Devices back to Android 5.1.1 Lollipop

Important: Do not forget to back up the data of your device, before performing a manual installation.

Requirements: ADB and Fastboot tools installed on your computer. You can use minimal adb and fastboot [Download here] for this purpose.

1. Download right Android 5.1.1 Lollipop factory image [HERE] for your device and unzip the file. Move all the contents to the same folder as the Minimal ADB and Fastboot installed on your computer (usually it will be C: – Program Files (x86) – Minimal ADB and Fastboot).

2. Enable “USB Debugging” on your device from Developer options menu.

3. Now, power off your Nexus device and enter into “fastboot” mode by holding down the Volume up + Volume down + Power buttons together.

4. Now, connect your phone to your computer via a USB cable

5. Go to the Minimal ADB and Fastboot folder and open a command window there (shift key + right click and select open command window here option).

6. If the LOCK STATE says locked, then type: fastboot oem unlock at the command prompt, and press Enter.

On your phone, choose “Yes” (use volume key) and confirm it by pressing the Power button.

[Note: This will ERASE your device, so make sure you have backed everything up first]

7. With the bootloader unlocked, you can install the Android 5.1.1 firmware. To do that, go to the Minimal ADB and Fastboot folder (where you have saved the unzipped factory image) and execute the flash-all script.

[This script installs the necessary bootloader, baseband firmware(s), and operating system]

On Windows: Run the file “flash-all.bat”.
On Mac: Run the file “flash-all.sh” using Terminal.
On Linux: Run the file “flash-all.sh”.

[Wait for the process to complete. The phone will reboot automatically]

Finally, you should lock the bootloader again for security. For that, boot your Nexus into fastboot mode, and then issue the command: fastboot oem lock