If you updated your LG Optimus L90 to the latest Android 5.0.2 Lollipop and it broke the root access, you now have a way to regain root access on the phone.

Regaining root access on the LG Optimus L90 is as easy as running a few commands from the Command Prompt Window. Here’s how it is all done:

LG Optimus L90

Files You Need

  1. You must have a Windows running computer to do this tutorial.
  2. You should have LG USB drivers installed on your Windows computer. If you do not, install them using the given link.
  3. This should work even if you are running the latest Android 5.0.2 Lollipop on your phone.
  4. Download LG Root to your computer. It is a package that contains everything you need to root your phone.

Rooting the LG Optimus L90 running on Android 5.0.2 Lollipop

  1. Unzip files from LG Root over to your computer by right-clicking on it and selecting Extract here.
  2. On your phone, head to Menu->Settings->About phone and tap on the option that says Build number for 7-8 times and it will say you are a developer. It unlocks the developer options menu on your phone.
  3. Now, head back to the main menu of Settings, tap on the option that says Developer options, and turn on the USB debugging option.
  4. Connect your phone to your computer using a compatible USB cable.
  5. Launch a Command Prompt Window in the folder where you have extracted LG Root files. To do that, open the folder, hold down Shift on your keyboard and right-click anywhere on your screen and select Open command window here.
  6. Type in the following command into the Command Prompt Window and press Enter:
    adb.exe devices
  7. It should show you the list of the connected devices. Make sure your phone is listed there or the following steps will not work.
  8. Next up, enter the following command into the Command Prompt Window to push some files over to your phone:
    adb.exe push busybox /data/local/tmp/ && adb.exe push lg_root.sh /data/local/tmp && adb.exe push UPDATE-SuperSU-v2.46.zip /data/local/tmp
  9. Once the above command has been executed, unplug your phone from your computer.
  10. Turn off your phone.
  11. Hold down Volume UP on your phone and plug in your phone to your computer.
  12. Your phone should now be in download mode.
  13. At this point, your computer should start installing the phone drivers. Wait for it to do that.
  14. When the drivers are installed, double-click on ports.bat that has come with the root package.
  15. It should tell you what COM number your phone is connected to. Note down that number for later use.
  16. Now, enter the following command into the Command Prompt Window replacing COM5 with the actual COM number that you have noted down.
    Send_Command.exe \\.\COM5
  17. Enter the following command and press Enter:
    sh /data/local/tmp/lg_root.sh dummy 1 /data/local/tmp/UPDATE-SuperSU-v2.46.zip /data/local/tmp/busybox
  18. It should gain root access on the phone.
  19. When done, pull the battery out of your phone.
  20. Put the battery back in your phone and power on your phone.
  21. Your phone should now be rooted!

Cheers! Your LG Optimus L90 running on Android 5.0.2 Lollipop is now rooted, all thanks to the LG Root script.

Now, open the Google Play store, find your favourite root-requiring apps, and install them on your phone. They will all work fine without any issues as you now do have root access on your phone!