[LG Optimus 4X HD] alexp999:
UPDATE: Unfortunately I no longer own this handset so am unable to test it against newer firmwares. If you find that this method does not work on firmware newer than V10D, try downgrading first.

I would like to begin this post, by saying that I did not come up with this method, but wanted to get it written up as a proper thread as soon as possible for people to start enjoying root on their phones!

This method was tested successfully by me on an EU phone running V10D. I am not responsible for what you do to your device after reading this guide. You undertake any actions at your own risk!

If you want to thank someone, please thank qaz753 who posted the method for this here.

All files needed are attached, the guide below is for Windows, but Linux and Mac scripts are included in the zip. (If certain files are not permitted to be attached, MODs please excuse and PM me, and I will look into hosting them myself)

GUIDE

Download, Unzip and Install the LG USB Driver.

Download and extract the Root kit (o4xr.zip) to "C:\o4xr"

Download and copy "IS11LG_SystemBackupTest.signed.apk" to your phone

On your phone, go to "Settings -> Security" and make sure "Unknown Sources" is TICKED

Go to "Settings -> Developer options" and make sure "USB debugging" is TICKED

Install "IS11LG_SystemBackupTest.signed.apk"

Open the "SystemBackupTest" app you just installed.

Hold the power button and choose "Power off and restart".

When you can see the lock screen, you may notice that the phone is running very slowly, this is normal.

Connect your phone via USB to your computer.

Make sure the phone is in "Charging Only" mode.

Open a command prompt (may need admin privelages, right click, run as administrator)

Type without quotes "cd C:\o4xr" and press enter.

Type without quotes "root" and press enter.

Wait while the script runs, and the phone will reboot automatically.

You should then see the command prompt "C:\o4xr>".

Uninstall the "SystemBackupTest" app on your phone. (Do NOT re-open it, or you will need to run the script again).

On your phone, open up Google Play Store and search for "SuperSU".

Update SuperSU then open it.

Press OK to update the SU binary.

You now have root and can safely restore the "Unknown Sources" and "USB debugging" settings back to how you had them!

The root kit and apk may contain other peoples work, I did a quick search to try and find the original sources but to no avail. If this is your work, please PM me and I will be more than happy to add your name to this post and give credit where its due. :)

HAVING ISSUES?

Try disabling any Anti-Virus you have running

Uninstall or disable any screen filters/adjusters

You can safely re-enable and re-install the above once you have completed root

If your device is really slow, make sure "USB Debugging" is ticked, then run in a command prompt:

REALLY SLOW AFTER ROOT?

Remove the "SystemBackupTest" app, if you haven't already.

On your phone, go to "Settings -> Developer options" and make sure "USB debugging" is TICKED

Connect your phone via USB to your computer.

Make sure the phone is in "Charging Only" mode.

Open a command prompt (may need admin privelages, right click, run as administrator)

Type without quotes "cd C:\o4xr" and press enter.

Type without quotes "adb shell rm /data/local.prop" and press enter.

Type without quotes "adb reboot" and press enter.

THANKS

qaz753, for posting this method!

atipon, for reducing the reboots to 1.

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