So, since the Optimus S for Sprint came out, we’ve had 2 over the air updates. If you’ve installed them, then all is fine and dandy. But today, we’re going to be rooting the very latest version of the Optimus’ software, LS670ZVC. Before you jump in, we ask that you read the whole guide thoroughly so you do not make a mistake. We don’t take responsibility for any error you make, so make sure you’re careful!

We’re going to do you a favor and help you get backups of your stuff before you update your phone, because it’s wiping everything! You’ll want to go to our article titled: Backing up Your Phone Before Root.

So, we’ve backed up our phones and we are ready to get the process under way to get rooted. Since we need to update our device to the version we want to root, we need to follow the guide to unroot our phone, located here.

Once you have unrooted and upgraded your phone all the way to the VC release, we will begin the root process, which will take a bit of time. You MUST have the Stock LG recovery installed or else you will brick your phone. If you followed our guide, you should already have it installed and need not worry.

We’re sure you’ll want a custom recovery program for your Optimus, so we’ve included instructions to install this as well. Please visit this link to get all the files you need for the root process of the VC release!

First, you need to unzip the Optimus Root folder to an easily accessible location, such as your C:\Android\tools folder. Then, take the 3b293d854446.LS670ZV8_V9_Inc file and unzip its contents directly to your SD card.

1) Open a command prompt. In that command prompt, enter the following commands, one per line:
cd C:\Android\tools
adb reboot recovery

2) In recovery, we want to scroll down to, and select, “apply sdcard:update.zip” which will fail, to trigger mounting the /system partition for the next steps.

3) Enter the following codes, one per line:
adb push rageagainstthecage-arm5.bin /sdcard/rageagainstthecage
adb push su /sdcard/su
adb push busybox /sdcard/busybox
adb shell
cd /sdcard
/system/bin/chmod 777 /sdcard/rageagainstthecage
./rageagainstthecage

3a) The last line of code should make your phone disconnect and reconnect twice. Wait about 2 minutes to make sure. If you know it did not do that, then enter this code (if that line worked, skip this line of code):
/sdcard/rageagainstthecage

4) Go into the shell again using the command below. The $ should turn into a #. If it does not, restart the process from step 1 above.
adb shell

If you got the # symbol, enter the following code:
/system/bin/mount -o remount,rw -t yaffs2 /system /system
cd /sdcard
./busybox cp su /system/bin
./busybox cp busybox /system/bin
cd /system/bin
/system/bin/chmod 4755 su
/system/bin/chmod 4755 busybox
exit
exit

Head over to the market and download the Superuser app by ChainsDD and install it!

Now we want to install the custom recovery you downloaded. Unzip flash_image.zip to your SD card. Also, unzip xionia_cwma_12518.4.zip to your SD card as well. Once those are in their proper place, we want to flash the recovery image now.

Enter the following codes, one per line:
adb shell
su (you will need to allow superuser permission on your phone. A screen will pop up.)
mount -o remount,rw -t yaffs2 /dev/block/mtdblock5 /system
cat /sdcard/flash_image > /system/bin/flash_image
chmod 755 /system/bin/flash_image
mv /system/etc/install-recovery.sh /system/etc/install-recovery.sh.bak
mount -o remount,ro -t yaffs2 /dev/block/mtdblock5 /system
flash_image recovery /sdcard/xionia_cwma_12518.4.img
reboot recovery

Note: if you get the following error — failed on ‘/system/etc/install-recovery.sh’ – No such file or directory — it is okay. It just means your recovery will not be erased by LG at any point in time.

To boot into recovery, when your phone is off, press and hold the following keys: Volume Down + Home + Power. Release the keys when the LG splash screen loads.

To navigate recovery, Volume Up and Down move your selection up and down respectively; Select is the Menu or Camera keys; Back is the back button.

Congratulations! That’s it!! You’ve now rooted the latest version of the LG Optimus software! Enjoy!

So, you need to unroot your LG Optimus S to take it in for service or update it or something? Here’s a descriptive guide to give you all the information and instructions to unroot your device.

First off, you will need to download some files, located here.

Once those files are downloaded, you will need to follow all of the following instructions. Failing to follow instructions may cause you to turn your Optimus into a paperweight.

Once we’re finished here, we will be reverted to a completely un-rooted phone, with the V8 software installed. We can then update our phone to V9 or the newest update, VC.

So, you’ve downloaded all the files that you need. Follow all of the below steps, and *absolutely* DO NOT skip any of them. They’re here for a reason.

1) Connect your phone to your PC and prepare to use ADB – open a command prompt, navigate to the directory where your ADB is located (ours is C:\Android\tools).

2) Unzip the recovery kernel and flash_image ZIPs you downloaded. Make sure the contents are inside of the C:\Android\tools folder, for easy access.

3) Enter the following commands, one per line:
adb push recovery-RA-GNM-thunderc-s-1.1.0.img /sdcard/
adb push flash_image /data/local/tmp
adb shell
su
chmod 755 /data/local/tmp/flash_image
/data/local/tmp/flash_image recovery /sdcard/recovery-RA-GNM-thunderc-s-1.1.0.img
reboot recovery

4) Your phone should now have rebooted into a recovery with light blue text, with Build: RA-thunderc-1.1.0-GNM at the bottom of the screen. Your controls are as follows:
Volume Up = Up
Volume Down = Down
Back = Back
Menu (4 squares button right of home) = Select

5) Scroll down to USB-MS Toggle. Select it.

6) Select USB-MS Toggle SDCard.

7) Unzip the nandroid-thunderc-V8-STOCK file and place the unzipped contents into the root of the SD card that should have popped up on your computer.

8) Use your option on your computer to safely remove the device (phone) from your computer.

9) Press the menu button to disable USB-MS toggle.

10) Press back.

11) Select Backup/Restore option.

12) Select Nand Restore

13) Select mem=477M

14) Select BCDMRS12-20101122-1915

15) Press Menu to confirm.

16) Wait. The restore process will take a while. When it is finished, DO NOT restart. We need to flash a STOCK RECOVERY now!!!

17) Enter the following commands, one per line:
adb shell
mount /sdcard (if this makes an error appear about device or resource busy, ignore it)
cd /sdcard/nandroid/mem=477M/BCDMRS12-20101122-1915
flash_image recovery recovery.img
reboot

Now, we have rebooted back into a stock build of the V8 software for the LG Optimus S. If you want to upgrade to V9, read below.

The process that we just completed upgraded our kernel. We need to update the firmware now to V9.

1) Plug your phone into you PC and enable USB mass storage.

2) Place the file named 3b293d854446.LS670ZV8_V9_Inc.zip onto your SD card, and rename it as update.zip (very important!).

3) Open a command prompt, and enter the following code:
adb reboot recovery
Note: this will only work if you followed our guide to install the SDK, or if you added ADB to your PATH variable in Windows. Otherwise, enter the following codes, one per line:
cd C:\Android\tools
adb reboot recovery

4) You should now be at LG’s recovery screen, which is dark blue text with 4 options. Select the option with update.zip.

5) follow the on-screen instructions, which are VERY IMPORTANT!!

You now have the V9 radio and baseband, as well as the stock update. You can delete that file that you remaned update.zip from your SD card, it’s no longer needed.

To upgreade from V9 to VC, use the LG Update tool.

This guide will explain how to root the LG Optimus. The process is really pretty simple, although other guides make it out to be really hard, or not for the novice user. Basically you’re going to need a few tools, up to an hour of free time, and a little bit of patience, as well as knowing how to red directions word for word and not skip anything. Also, these instructions are from a Windows 7 based computer. I’m actually going to root the LG Optimus as I write this guide, so I know these steps are correct!

The very first steps we need to take are as follows:

• Download and install the Java Runtime Environment (JRE)
• Once JRE is installed, we now need to download and install the Android SDK. Follow steps on How to Install Android SDK here.
• Once the SDK is installed, according to our instructions, you need to isntall drivers to make the computer recognize your LG Optimus.

So, we need to download the LG Mobile Support Tool. Once it’s downloaded, install it. Once the program is installed, and while your phone is not connected to your computer, open the program. This is going to take a few minutes to load the program. We need to change some settings in it to make it work right.

Under the Options & Help menu, choose Country & Language. Set United States as your country, and English as your language. Next, on the main window choose to install the USB driver, and choose Sprint as the carrier, and LGLS670 as the model number. Now, wait until the application downloads and installs some drivers for your phone. Once it installs the drivers, close the program. You no longer need to run it.

While you wait for the files to download, you can begin prepping your phone to be rooted and connected to your computer. Go to Menu > Applications then select Unknown Sources. This allows us to install applications to your phone from the computer. Place a check in the box. Then, accept the warning. Next, go to Development, then select USB Debugging. This allows us to root the phone. After you do that, and the program is done installing the USB drivers, plug in your phone once, let it do it’s thing and let the computer install all the drivers for it, then when you get a message saying your device has been installed successfully, unplug your phone, then plug it back in one minute later to make sure everything is ok.

The next thing we need to do is download the root files. You can obtain them here, named OptimusRoot. Once you download this file, extract it and copy the 3 files inside to your C:\android\tools folder. Now, connect your phone to the computer if you haven’t already, Make sure it says USB Debugging Connected or something along those lines in your notification pulldown.

Next, launch the Android SDK Manager, which is also located in the C:\Android\ folder of the Android SDK program you downloaded earlier.

Next, open a command prompt (if you don’t know how, here’s How to Open a Command Prompt) and type the following commands, one per line:

cd C:\Android\tools
adb push rageagainstthecage-arm5.bin /data/local/tmp/rageagainstthecage
adb push su /data/local/tmp/
adb push busybox /data/local/tmp/
adb shell
chmod 4755 /data/local/tmp/rageagainstthecage
chmod 4755 /data/local/tmp/busybox
cd /data/local/tmp
./rageagainstthecage

Now, let everything rest for a couple minutes. This is going to disconnect your ADB session once finished, so after 2-3 minutes, type the following:

adb shell        \\Note: This should now return a # instead of a $. If this does not work, repeat the command prompt steps.
mount -o remount,rw -t yaffs2 /dev/block/mtdblock4 /system
cd /data/local/tmp
./busybox cp su /system/bin
./busybox cp busybox /system/bin
cd /system/bin
chmod 4755 su
chmod 4755 busybox
busybox –install /system/bin
exit
exit

Note: If you get to this step “busybox –install /system/bin” you get an error, do this:

a) Download superuser (free) from chainsDD in the market (this is step 5 below)
b) Download Titanium Backup (free) in the market
c) Launch Titanium Backup. You should get a request to give it root permissions. select always allow. Now in Titanium Backup, hit the “problems” button and let it install busybox
d) Reboot phone and enjoy

If you didn’t have any problems with the installation of everything so far, then please go to the Android Market and download the Superuser app, made by the author ChainsDD.

Enjoy root!

LG Mobile Support Tool

OptimusRoot