How to Flash TWRP and Root LG V20 (LS997, VS995, H910, F800L) | Guide.

Install TWRP & Root LG V20. This guide will show you how to flash or install TWRP recovery on Android LG V20 smartphone. TWRP recovery is one of the popular recoveries for Android device, recovery will allow the user to install custom ROM, flash TWRP, or flash any zip file contains root script. Also, the user will able to take a full Android backup or called Nandroid, it will restore the Android phone if fail or soft brick. LG V20 restrict the user to flash TWRP recovery directly from fastboot mode, therefore unlock bootloader is needed before flash TWRP on LG V20 device. 

Follow this guide only on the following LG V20 versions;

• LG V20 for Sprint LS997
• LG V20 for ATT H910, 
• LG V20 for Verizon VS995, 
• LG V20 for Korean F800L, 

Thanks' for me2151 as XDA user along with other developers for this guide.

http://forum.xda-developers.com/v20/development/ls997vs995h910-dirtysanta-bootloader-t3519410

Prerequisites.

1. TWRP-3.0.2-1-us996.img - here

http://redirect.viglink.com/?format=go&jsonp=vglnk_148232856136724&key=f0a7f91912ae2b52e0700f73990eb321&libId=iwyypnug01000n4o000DAap9oxpi3&loc=http%3A%2F%2Fforum.xda-developers.com%2Fv20%2Fdevelopment%2Fls997vs995h910-dirtysanta-bootloader-t3519410&v=1&out=https%3A%2F%2Fbuild.nethunter.com%2Ftest-builds%2Ftwrp%2Flge%2Ftwrp-3.0.2-1-us996.img&ref=https%3A%2F%2Fwww.google.com%2F&title=%5BLS997%7CVS995%7CH910%7CF800L%5D%20DirtySanta%20Bootload%E2%80%A6%20%7C%20LG%20V20&txt=TWRP

2. V20-root.zip - Here

http://redirect.viglink.com/?format=go&jsonp=vglnk_148232856719425&key=f0a7f91912ae2b52e0700f73990eb321&libId=iwyypnug01000n4o000DAap9oxpi3&loc=http%3A%2F%2Fforum.xda-developers.com%2Fv20%2Fdevelopment%2Fls997vs995h910-dirtysanta-bootloader-t3519410&v=1&out=https%3A%2F%2Fwww.androidfilehost.com%2F%3Ffid%3D457095661767122821&ref=https%3A%2F%2Fwww.google.com%2F&title=%5BLS997%7CVS995%7CH910%7CF800L%5D%20DirtySanta%20Bootload%E2%80%A6%20%7C%20LG%20V20&txt=v20-root.zip

3. The latest SuperSU Here

https://download.chainfire.eu/1014/SuperSU/SR5-SuperSU-v2.78-SR5-20161130091551.zip

4. for Sprint version LG V20 (LS997) only.
• LS997-deODEXd-signed.zip Here

http://redirect.viglink.com/?format=go&jsonp=vglnk_148232859369531&key=f0a7f91912ae2b52e0700f73990eb321&libId=iwyypnug01000n4o000DAap9oxpi3&loc=http%3A%2F%2Fforum.xda-developers.com%2Fv20%2Fdevelopment%2Fls997vs995h910-dirtysanta-bootloader-t3519410&v=1&out=https%3A%2F%2Fwww.androidfilehost.com%2F%3Ffid%3D673368273298916556&ref=https%3A%2F%2Fwww.google.com%2F&title=%5BLS997%7CVS995%7CH910%7CF800L%5D%20DirtySanta%20Bootload%E2%80%A6%20%7C%20LG%20V20&txt=LS997-deODEXd-signed.zip

5. This guide required ADB and fastboot installed on the computer, ADB and fastboot for windows or Mac available here. extract all file in the same folder. for example c:\fastboot

http://forum.xda-developers.com/android/software/host-tools-t3402497

Step by Step Flashing TWRP.

1. Unlock bootloader LG V20. (required) - Here

http://guidebelajar.blogspot.com/2016/12/guide-unlock-bootloader-lg-v20-vs995-h910-f800l-ls997.html

2. Extract or unzip V20-root.zip to the specific computer folder.
3. Then copy all file to the V20-root folder.
4. Now, put all file above inactive ADB directory as mentioned above. (c:\fastboot)
5. Connect LG V20 to the computer using the USB cable.
6. Open the command prompt from ADB and fastboot directory, how to do it?
• Press and hold the shift button and right click mouse on empty or blank space.
• Then select Open command window here.
7. Next ;
• For Window.
• Double click to run Step3.bat. so TWRP can be flashed and a working boot.img flashed.
• For Linux.
• Open the terminal, and type the following code below.

./Step3.sh
# OR
Bash ./Step3.sh

8. If on this step you get the message that says <waiting for device>. make sure fastboot driver installed on your computer or laptop.
9. How to fix the problem in step 7?
• Go to device manager. while the LG V20 is connected in fasboot.
• Then right-click the item that says Android 
• Now select update drivers
• Select update from the internet.
• Just wait for device manager to install the drivers.
10. Once driver installed on the computer, you can return to step 6. (run step3.bat) to try again.
11. Now reboot your LG V20 phone, when this device back to lock screen type the following code at the command prompt.
• adb reboot recovery
12. THIS STEP FOR SPRINT ONLY
• Sprint users will have a constant phone app crash.
• Therefore, You should still have ADB access.
• If you don't have ADB access, do the following;
• Open LG V20 back cover
• Remove battery then reinsert again
• Press and hold volume down button while connecting to the computer.
• Open command prompt then types the following command. 
• fastboot erase system 
• fastboot reboot
• Your LG V20 device will reboot to an LG screen. Keep checking ADB devices for your device. then type the command;
• adb reboot recovery
• End of Sprint guide.
13. Now your LG V20  phone should display a red triangle and say corrupt, then it will boot into TWRP.



red triangle corrupt warning

14. Once LG V20 enter TWRP, Press Cancel on the password prompt and then swipe to allow system modifications.
15. If you wish to create a backup on this step, You must save it on SD card, and you cannot backup the data partition.
16. Once a backup is completed, now return to the TWRP main menu.
17. Tap Wipe button - Select Format Data
18. On the next step will differ, depending on what LG V20 model you have
1. For LG V20 Sprint(LS997), follow this step.
• From TWRP main menu, Tap Wipe - Advanced - Check Dalvik System, Data, and Cache - Then Slide to Wipe.
• Back to TWRP main menu, Tap Wipe - Format Data - Type Yes to continue
• Back to TWRP main menu, Tap Install - Flash the “LS997-deODEXd-signed.zip” file. - 
• Then Flash SuperSU.Zip
• Go back to back to TWRP main menu - Tap Reboot - System
2. For LG V20 Verizon (VS995) and ATT(H910), follow this step
• From TWRP main menu, tap install to flash SuperSU.zip
• Back to TWRP main menu, Tap Wipe - Format Data - Type Yes to continue
• From TWRP main menu, Tap Wipe - Advanced - Check Dalvik System, Data, and Cache - Then Slide to Wipe.
• Go back to back to TWRP main menu - Tap Reboot - System
19. These instructions are for all device again.
20. First boot after flashing SuperSu will show the Red triangle twice.Wait for system to boot (this will take a while)
21. It may appear like the system has frozen but it has not. Don't worry just wait.
22. For Verizon User
• If your LG V20 Verizon encountered abnormally long first boot time, approximately 20 minutes before first time setup. You can resolve this issue.
• Boot into bootloader, how to do it?
• Pull the battery and insert it again,
• Press and hold Volume Down while connecting LG V20 to the computer.
• Then type the following command ;

• fastboot flash boot boot2.img
  fastboot reboot

23. For All User.
• If you encounter a -Secure Boot- Password then booting the first time you did not Format data properly.
• To reiterate: To properly decrypt the LG V20 device you need to boot into TWRP
• Then go to Wipe - Format Data
• You will be prompted to type "yes" to format and decrypt.
• Once you are booted and have proceeded through the setup wizard, re-enable Android Debugging (ADB) if not already enabled.
• Then type the following command below.
• adb reboot bootloader
• Once your LG V20 enter bootloader, now type ;
• fastboot flash boot boot2.img
• Once you see the result is finished, now type;
• fastboot reboot
• The LG V20 phone will boot back into the system.
24. This step is required, It will it prevents background crashes and fix's battery drain.
• Once full booted back into android, Type;
• adb reboot recovery
• Once your LG V20 phone enter TWRP menu - Tap Install - to Flash SuperSU.zip - Then Go back
• From TWRP main menu, Tap Wipe - Advanced - Check Dalvik System, Data, and Cache - Then Slide to Wipe.
• Go back to back to TWRP main menu - Tap Reboot - System
25. Now your LG V20 (LS997, VS995, H910, F800L) phone is rooted.
26. Download your favorite root checker to verify root status