[GUIDE/TOOL] Unlocking Bootloader & Recovery - LG Optimus L9 P760, P765, P768, P769

Hello everyone, I've been messing with this phone for a long time now, and hopefully my findings will help some poor soul unlock the bootloader.
I'm not going to go into the whole setting up and using the offline flash (R&D Tool). There are several threads on the subject. I will provided some links later (or I may make some instructions later later).
Okay I've noticed that the system has not been getting overwrite properly with the offline flash.
My bootloader is unlocked and I recently performed an offline flash of Euro 20B. While I'm on that kdz I have permission to reboot into the bootloader whenever I want.
Well to my surprise, I couldn't enter the bootloader anymore. I tried a hard rest and several other minor things and nothing seemed to work.
So I solved the problem by replacing the system image using the Linux DD command.
This script will
1. flash the unaltered 20B u-boot, boot, recovery & system images
2. install/fix busybox thanks to @Phil3759 Busybox Uninstaller v1.0
3. install bootstrap recovery (cwm), thanks to @artas182x L9 Recovery Installer
4. root with Cydia Impactor
5. issue the unlock command
6. will fix the damage caused by flashing the euro kdz (thanks to @Lelus).
Click to expand...
Click to collapse
Note: this tool was made for *769 models, but any L9 model can use the main program, just don't use the cwm flashable zips.
Warning I am not responsible for any damage that may arise by using this script, use at your own risk!
I have took several precautions, but anything can go wrong with computers.
Things you will need:
Micro SD with at least 1.3G of free space OR an empty data partition (Internal SD).
CWM Backup for your device
Disable/Remove any Internal/External swap
Brain
Note: Please do not place any img files inside the 1KUMA folder or the system flash will fail
Here are the steps and good luck.
1. Perform the offline flash of Euro 20B kdz.
For *769 models
(To make things go smoother, disable pattern/pin lock screen, start off on any jellybean kdz, and enable show touches.)
2. Open Start.cmd (double click), and root with cydia impactor. (USB debugging should still be enabled)
3. Select yes to replace the system image, and wait a very long time (approximately 13 mins).
4. Reboot phone (must reboot) and root again with Cydia.
5. Skip install of system, push flashable files to External or Internal SD (only for *769 models), install busybox and recovery.
6. Reboot phone and flash radio zip (for *769 models only) if needed. Actually this step can be performed before flashing the system.
7. Play with the phone for about 45mins. Turn on data, open a browser, turn Wi-Fi on for about 10 mins. Don't rush this step.
8. Run the script to the very end (skip system flash & pushing cwm files), and select the reboot option to unlock bootloader.
Here are the steps I would try if I got my hands on a locked phone
1. Have root or root your current ROM (kdz)
2. Open Start.cmd (Enable USB Debugging and connect phone in LG software mode.
3. Flash 20B euro images
4. Reboot phone and root again with Cydia
5. Play with the phone for about 45mins. Turn on data, open a browser, turn Wi-Fi on for about 10 mins. Don't rush this step.
6. Run Start.cmd and select the last option to unlock bootloader.
Update
Please download this zip Patch2.zip
and replace the corresponding files (Start.cmd, 1flash-system.sh, 2flash-system.sh)
Click to expand...
Click to collapse
Here are the links
Kuma82-Recovery.zip 587.0 MB
Mega Link
Mediafire Link
P769 & LGMS769 models please read second post

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Here are the instructions for recovering from the V20B kdz
For P769 & LGMS769 models
1. Have your cwm backup (or my themed stock) already on your external or internal SD.
2. Run Start.cmd, push files (Fix_Touch-V20F.zip & MetroPCS-V10E-Radio.zip) to Internal or External SD.
3. Install busybox and reboot into the inverted cwm recovery.
4. Navigate (use a mirror if needed) through cwm, restore your choice of #1, and reboot into recovery again (press "vol -" at blinking lights).
Note: CWM will not be inverted
5. Install Fix_Touch-V20F.zip & MetroPCS-V10E-Radio.zip (if needed).
6. Reboot
These 6 steps will fix the inverted LG Logo & wonky touchscreen.
We owe @Lelus a HUGE thanks for creating his touchscreen fix, custom recoveries and so much more. :highfive:
We also owe a HUGE thanks to @artas182x for creating/porting the 2nd init (bootstrap) cwm recovery. :highfive:

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Going to try it out now man! AWESOME WORK!

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We look forward to the results I understand that the program overwrites the current rom newest version V20B?

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I may finally try again this weekend! THANK YOU!!!!
Sent from my LG-P769 using XDA Premium 4 mobile app

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Help?
Okay. So, I did this while using your ROM (10e), it just ended the script and I'm in the OS and such now. But, my boot logo was NOT inverted and my touches are fine. Did you have these set to fix themselves automatically? Or did something go wrong? D:
I'm leaving WiFi on for now, and Data as well. I leave in 30 minutes to go (tutoring, lol sigh) and when I get back I'm going to try and seal the deal, if, IF it actually worked. If this works I swear, I will cry tears of sweet, sweet joy.<3

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Ilxaot said:
Okay. So, I did this while using your ROM (10e), it just ended the script and I'm in the OS and such now. But, my boot logo was NOT inverted and my touches are fine. Did you have these set to fix themselves automatically? Or did something go wrong? D:
I'm leaving WiFi on for now, and Data as well. I leave in 30 minutes to go (tutoring, lol sigh) and when I get back I'm going to try and seal the deal, if, IF it actually worked. If this works I swear, I will cry tears of sweet, sweet joy.<3
Click to expand...
Click to collapse
Yeah, the fixes are included but you must confirm the installation. Just tried with no success. But I was on V20H, I'll flash V20B and start all over.
Anyways, thanks a lot for your work Kuma!
Sent from my LG-P760 using xda app-developers app

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No luck, it seems like nothing is getting flashed, when asked to reboot phone, its still on, I hold the power button and click reboot, the script says to remove the battery if necesary, so I guess it should be in fastboot or something like that. I'll keep on trying. :banghead:
Good luck to you all.
Sent from my LG-P760 using xda app-developers app

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Tried again, and it just boots into recovery when trying to unlock.. :/

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Ilxaot said:
Okay. So, I did this while using your ROM (10e), it just ended the script and I'm in the OS and such now. But, my boot logo was NOT inverted and my touches are fine. Did you have these set to fix themselves automatically? Or did something go wrong? D:
I'm leaving WiFi on for now, and Data as well. I leave in 30 minutes to go (tutoring, lol sigh) and when I get back I'm going to try and seal the deal, if, IF it actually worked. If this works I swear, I will cry tears of sweet, sweet joy.<3
Click to expand...
Click to collapse
Everything should be inverted, it must have not passed one of the checks. If you start of on my ROM you must remove the swap script.
Sent from my LGMS769 using XDA Premium 4 mobile app

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HereticSins said:
Tried again, and it just boots into recovery when trying to unlock.. :/
Click to expand...
Click to collapse
Sorry to hear this. May you please give me the exact steps you took. I may be able to help ya.
Corrado27 said:
We look forward to the results I understand that the program overwrites the current rom newest version V20B?
Click to expand...
Click to collapse
Yes it flashes the u-boot, boot, recovery, and system images, I extracted from the Open V20B kdz
Sent from my LGMS769 using XDA Premium 4 mobile app

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vitorcruzbr said:
No luck, it seems like nothing is getting flashed, when asked to reboot phone, its still on, I hold the power button and click reboot, the script says to remove the battery if necesary, so I guess it should be in fastboot or something like that. I'll keep on trying. :banghead:
Good luck to you all.
Sent from my LG-P760 using xda app-developers app
Click to expand...
Click to collapse
Please give me the exact steps you took. Did you get any message like "corrupt images"?
Sent from my LGMS769 using XDA Premium 4 mobile app

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I just thought of some modifications I can make to improve the start.cmd
Sent from my LGMS769 using XDA Premium 4 mobile app

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kuma82 said:
Please give me the exact steps you took. Did you get any message like "corrupt images"?
Sent from my LGMS769 using XDA Premium 4 mobile app
Click to expand...
Click to collapse
Yes, everytime.
1. Reflashed V20B.
2. Plugged in with debugging activated.
3. Run your script, rooted, pushed the files to external sd, then it says some file is missing and I have to run that step again (everytime the same file, I even tried a different computer) but I checked and it was there, but the phone doesn't reboot or anything. Then I wait 45 minutes and the phone reboots to recovery.
Obs: my phone is P768, I even flashed V10A and then V20B to see if it works, but I guess my phone really is made by the devil, as Lady Vengeance says haha.
Sent from my LG-P760 using xda app-developers app

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Working on LG L9 P760?

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Reboot to recovery

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rufik1920 said:
Reboot to recovery
Click to expand...
Click to collapse
+1
I hope you will manage it to work

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kuma82 said:
I just thought of some modifications I can make to improve the start.cmd
Sent from my LGMS769 using XDA Premium 4 mobile app
Click to expand...
Click to collapse
So which KDZ should I flash in order to attempt this?

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Ilxaot said:
So which KDZ should I flash in order to attempt this?
Click to expand...
Click to collapse
As per the instructions, it should be the same v20b euro open rom that you would usually use to attempt the unlock.
I know people were having trouble downloading it before, so I'm uploading a copy right now. Will edit my post with the link. Does anyone know if there is any rule against posting a link to a file stored on my own server/domain?
(went with a filesharing site, since I wasn't sure about the rules on that other thing)
Get it while it's hot: V20B Europe Open Rom
Code:
https://mega.co.nz/#!VNFyhQJB!GhCl_zyWTHNwAlHeomUHoW5Ve75hYUsuCOXWnvKP39E

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vitorcruzbr said:
Yes, everytime.
1. Reflashed V20B.
2. Plugged in with debugging activated.
3. Run your script, rooted, pushed the files to external sd, then it says some file is missing and I have to run that step again (everytime the same file, I even tried a different computer) but I checked and it was there, but the phone doesn't reboot or anything. Then I wait 45 minutes and the phone reboots to recovery.
Obs: my phone is P768, I even flashed V10A and then V20B to see if it works, but I guess my phone really is made by the devil, as Lady Vengeance says haha.
Sent from my LG-P760 using xda app-developers app
Click to expand...
Click to collapse
I may have made a mistake, I've did a lot testing but anything is possible. I won't be able to fully check on the problem until tomorrow (working a double right now and i have to sleep for a bit and right back to work :/ ).
Have you tried using the internal SD?
Sent from my LGMS769 using XDA Premium 4 mobile app