With the latest Android OS launched by Google and the older Nexus devices getting the update many Nexus having Nexus 5, Nexus 6, Nexus 7 and Nexus 9 users have upgraded to Android 6.0 Marshmallow. With this being the Beta version many users might not be liking the new OS just for the bugs or the OS feel as well and if you are one of them, here is a tutorial to get back the Android Lollipop 5.1 to your Nexus devices.
We will be showing you in steps on how to downgrade your firmware from Android 6.0 Marshmallow to Android 5.1 Lollipop. You need to have knowledge about Flashing firmware manually to get this done. Make sure you back up your device completely before starting the procedure to make sure that you do not lose any data if something goes wrong in the procedure.
Steps to Downgrade Nexus Devices from Android 6.0 Marshmallow to Android 5.1 Lollipop:
Files required: ADB and Fastload tools installed in your Laptop or PC. Which can be downloaded from XDA forum – Download here
Download the Android 5.1.1 Lollipop factory image from official Google developers website – here. Select the exact version of your Nexus device to download the related file (the list is given).
Find the location of the ADB and Fastload files and move the downloaded Android 5.1 Lollipop factory image as well. Mostly the location will be in C: Program Files – Minimal ADB and Fastboot.
Take your Nexus device and Enable “USB Debugging” which should be done by accessing the Developers options menu and activating the USB Debugging option.
Turn your Nexus device Off and you need to hold the Volume Up + Volume down + Power button together to enter the Fastboot mode.
After your Nexus is in Fastboot mode, connect it to your Laptop or Computer using a USB cable.
You have to now open a command window in the Minima ADB and Fastboot folder, this can be done by pressing the shift key + right click and select open command window here.
Sometimes you will be getting Locked message in Lock State which should be unlocked by typing: “fastboot oem unlock” in the command prompt
Note: The next step erases all your data on your device, so go ahead only if you have backed up your data before hand.
Now you have to choose “Yes” in your smartphone which can be done by navigating with the volume keys and selecting with the power key.
Now it is time to install Android 5.1.1 firmware as the bootloader is now unlocked. You have to execute flash-all script by going to the Minimal ADB and Fastboot folder. This is different for each type of OS, if you are using Windows: Run the file “flash-all.bat”, in case you are using Mac: Run the file “flash-all.sh” using Terminal, for Linux users: Run the file “flash-all.sh”.
Once the process is completed your Nexus device will reboot automatically and you have to make sure to lock your bootloader again for security reasons which is done by issuing the command: fastboot oem lock.
That is it, you have now successfully Downgraded your Nexus 5, Nexus 6, Nexus 7 or Nexus 9 device from Android 6.0 Marshmallow to Android 5.1.1 Lollipop. Do let us know if you are facing any issues with the procedure or have any easier way to do it, in the comments section.