yashsingh1/xdaforums huggingface dataset:
[LG V40 Guides, News, & Discussion] racer8dan:
I got it figured out now, I got fastboot mode back by erasing the laf_a partition, now i got twrp installed and am ready to flash roms, the only issue now is when i flash lineageos 17 or 18 i get a bootloop, though i heard that i must have a base android version 10 and not 9 so i am going to try installing verizon Q kdz and trying again. Thanks for the response
[LG V40 Guides, News, & Discussion] Sherzaman Khan:
@Xsavi

Is we unlock bootloader in android 10 in 409n korean version without any problems?
[LG V40 Guides, News, & Discussion] junejo46726:
yes

is we...
[LG V40 Guides, News, & Discussion] bsteph27:
(french) hello i read your topic and i have problem.

with the tool partition manager step i have error fiunction main 320. like this picture.

and i dont find the rawprogram0.xml.

please help i read some pages and i don't find the answer.
[LG V40 Guides, News, & Discussion] AsItLies:
What you're experiencing is pretty common, a sahara error. There are numerous reasons that cause that error. This is a direct quote of the information available on the v40 tele group for this error:

"When you get a sahara error on Qfil, change your USB port/cable.

Restart both phone and pc before trying again.

Check drivers on PC

Try reducing the COM port speed by going to device manager

Try another PC

Disable driver signature verification on Windows 10

If you run out of ideas, use a Linux installation; will save you a lot of trouble"

Also, there is not rawprogram xml needed unless you are flashing a complete backup to the phone, for most of the purposes we use qfil for, it's not needed.

cheers
[LG V40 Guides, News, & Discussion] bsteph27:
(french) hello i read your topic and i have problem.

with the tool partition manager step i have error fiunction main 320.

thank you very much.
[LG V40 Guides, News, & Discussion] bsteph27:
thank you for your help

now i have a problem with fastboot. I manage to start with this menu.

problem my device is not recognized by device manager he name this "android" with USB \ VID_18D1 & PID_D00D

USB\VID_18D1&PID_D00D driver download

USB\VID_18D1&PID_D00D driver download for ANDROID BOOTLOADER INTERFACE

download-drivers.net

fastboot commands which work the phone only reboot with this message error and return in this menu.

update. windows is ****ty with adb fastboot. i retry with a linux ubuntu desktop i install adb ect it work perfectly. i try to flash twrp with fastboot at present.

please help
[LG V40 Guides, News, & Discussion] shamnh:
MIne got red tag. I forgot to save the current abl_a file before proceed. any body got backup for abl_a for G710AWM30b_00_OPEN_CA_OP_0605.kdz ( Android 10) please share with me. I really apprieciate it. right now im stuck with fastboot and also manage to access qfil.
[LG V40 Guides, News, & Discussion] AsItLies:
Don't think you'll find anyone in this thread with partitions for the G7. You might look into the kdz extractor utility. It can dump all the files within a kdz, could be much easier to find what u need.

cheers
[LG V40 Guides, News, & Discussion] iannisb:
I ve installed your QPST but i still get this error Download Fail:Sahara Fail:QSaharaServer Fail:Process fail
[LG V40 Guides, News, & Discussion] AsItLies:
qfil is a pain, but great to have after the effort. So sahara errors can happen for various reaons. 1) is the qualcomm driver not being signed, so use this one, as it's signed. Reboot afterwards.

another possibility is needing a usb 2.0 port, not 3.0. The sftwr was designed long ago, it needs old hdwr. And some have finally had success by using a different computer! It's that big of a pain.

but I have it on 2 boxes, one with win 8.1 and other win 10. It can be done, need patience ;)
[LG V40 Guides, News, & Discussion] Wind_Gum:
"Your device softwear cannot be checked for crruption. Lock the bootloader."

My phone shows this status when booting. its mean my bootloader has been looked??. please help me. I'm not good at English:cry::cry:

LMV405UA-verizon
[LG V40 Guides, News, & Discussion] AsItLies:
Yes, it means the bootloader is unlocked. There's no way to get rid of the message, just something you'll see everytime you boot the device.
[LG V40 Guides, News, & Discussion] sptw:
Hi there,

I own a LG V40 409N Korea Version. I bought it from second hands. It is new. It came with android 10. I roll back to android 9 pie using LGUP. Works fine. No problem at all.

So, i tried the guide here from Xsavi ( thanks for your hard job on it ). I could reach to install V35 Engineering Bootloader on device. Fastboot show V35 bootloader is there. After the operation the PC do not recognize the device anymore, so, i can not reach fastboot on ADB to unlock de the bootloader.

I understand if the V35 bootloader uploaded to the smartphone, ADB should be able to reach fastboot in device, but no, no way.

It seems it could be a driver problem. At least for me it seems a driver problem, but i installed all the drivers possible. LG USB driver isthere. ADB and FastBoot driver is there. Qualcom signed driver is there. In normal usage with Android pie, windows 10 can see the smartphone. I can do all of the operations possible. Operational System recognize the devices in download mode, in EDL mode, and return for me the device number using " adb devices " on cmd command line. Fastboot mode ... NO. On device ( smartphone ), it says " no commands ). I understand it as a pie bootloader locked. If i install V35 Engineering Bootlaoder on it, i can reach fastboot mode, but the PC do not recognize the smartphone.

What do you think abou it? Really a drive problem? About a driver, i can not elaborate it anymore. I tried everything. Maybe i am doing something wrong on it.

I forgot to say that on V35 Bootloader , the device ( smartphone ) is recognized as " Android " waiting for a drive ( yellow exclamation ). I tried the gogle adb devices and those with pre installed on OS ( Windos 10 ).

The last thing: Windows 7 and Linux ( Kubuntu )do not recognize the device too.

As soon as i revert to the original firmware Android 9 Pie, everything runs like a charm and device is recognized in all of your way ( not fastboot mode).

May someone ellaborate it better than me, please. I really need a help or an opinion here.

Thanks in advance.
[LG V40 Guides, News, & Discussion] sptw:
In time: I found the culprit. It is really a driver issue and windows 10. I found this thread and the solution is on the 7 step:

Bootloader Unlock and Root Instruction - No Octoplus Box Required | XDA Developers Forums (xda-developers.com)

Althought the driver is for windows7, it works for me in compatibility mode.

I could unlock the smartphone e upload the ablpiestock.image.

Now a new problem...

Start the device and the red triangle is there showing: both slots are unbootable. I Wait for a time but nothing happens. Device power off after a time.

Time to rest.
[LG V40 Guides, News, & Discussion] AsItLies:
It sounds like you have mismatched partitions. The v35 engineering abl is 'Oreo'. So if you have that on slot a (and b), the phone will not boot (unless the OS version is oreo).

The intention of the v35 eng abl is to use it to unlock the bootloader, then replace it with the original abl_a of the OS version you currently have installed.

In other words, it's not meant to be a permanent replacement, only temporary.

cheers
[LG V40 Guides, News, & Discussion] sptw:
Thanks for reply AsItLies,

It was my fault. I forgot to exit partition manager in Qfill as soon as the device got V35 Engineering Bootloader. So, in the truth, the device was not unlocked. Today i repeated the entire process again and the smartphone is unlocked now.

Thanks so much for the help here and there AsItLies.
[LG V40 Guides, News, & Discussion] nikothebarber:
im getting a pop up when i click on the partion manager "please make sure you have selected the correct programmer in the flat build page" I have firehouse.elf file on my desktop and loaded properly into the programmer, what did I do wrong?
[LG V40 Guides, News, & Discussion] sptw:
Nothing wrong. It works in this way. Click yes and continue the process.
[LG V40 Guides, News, & Discussion] nikothebarber:
it failed
[LG V40 Guides, News, & Discussion] sptw:
Failed the entire process? It does not pass V35 Engineering Bootloader process? What says? Sahara failed?
[LG V40 Guides, News, & Discussion] nikothebarber:
Did I **** up? is the v35 engineering mode where you enter the oem unlock code suppoused to say secure start up at the top
[LG V40 Guides, News, & Discussion] nikothebarber:
after inputing code and waiting the phone rebooted to a white screen
[LG V40 Guides, News, & Discussion] nikothebarber:
ok rebooted again now in safe mode on secure start up screen
[LG V40 Guides, News, & Discussion] osaka35:
phone won't reboot to fastboot. no errors and everything seems to be successful after following directions. just boots to android 10 like usual.

V40 ATT with bootloader unlock enabled in developer, with adb enabled. Everything goes smoothly up to when I try and reboot to fastboot. v35engineering writes successfully to abl_a in ufs mode. after successfully flashing, I timed it so i release the power button at the same time it disconnects from windows. 12 seconds for me, and that's the absolute earliest I can do it and it still reboot. whether I do it immediately after flashing in QFIL, or exit it and do its closing out stuff, no difference. Any advice would be appreciated.
[LG V40 Guides, News, & Discussion] AsItLies:
Yeah it's pretty clear then, for a couple of reasons, that your current boot slot must be b.

The give-a-way is that u say 'just boots to android 10 like usual'. And that u flashed v35 eng abl successfully to abl_a. See, that's the thing, the v35 eng abl will only boot your device if the OS is Oreo. No other OS will boot, just Oreo.

So you've probably done at least 1 ota update? That's why you'd be on b. It's easy to fix, just use qfil to flash v35 eng abl to both a and b, then do the key combo to get to bootloader. Once in fastboot do 'fastboot getvar all' And towards the bottom of the output it will tell you 'current slot' that is active.

cheers

oh and be sure to then use fastboot to flash the original abl back to a and or b, so the phone will boot. You can leave it on the inactive slot if desired, that way you can have it to use if needed.
[LG V40 Guides, News, & Discussion] nikothebarber:
when trying to go into fast boot mode after flashing v35 img im stuck on secure start up, my device is ATT variant and it was on stock 10. please help me
[LG V40 Guides, News, & Discussion] nikothebarber:
ok now im back oin 9009 and back in the partion manager screen what should I do from here reflash v35 abl-b? or what
[LG V40 Guides, News, & Discussion] MMonika:
I am now stuck with the pie bootloader unlocked but can't boot normally anymore. I can get into 9008.

Any way out?

Edit: set my active slot to a and be able to boot normally. But now I can't go into fastboot anymore. bootloader is still unlocked.

Edit 2: I must nuke laf in order to get into fastboot after unlocked. I installed TWRP
[LG V40 Guides, News, & Discussion] Unknown2803:
Does this work on Android 9?
[LG V40 Guides, News, & Discussion] waqashaseeb:
Bhai muja aap ke help chyea haa.
[LG V40 Guides, News, & Discussion] waqashaseeb:
Contact me Please +923359999693
[LG V40 Guides, News, & Discussion] waqashaseeb:
I have LG V409N on Android 10 is it going to work.
[LG V40 Guides, News, & Discussion] AsItLies:
So, which part of "Every variant" didn't you get? Not to be rude but if it says every variant except, and your's isn't one of the 'excepts', then it's going to work, right?

Mine is running 409n a10, it works. If it didn't work, the title would be updated.

cheers
[LG V40 Guides, News, & Discussion] VnNhn97:
I have LG V409N on Android 10 bootloader is unlocked

help me root
[LG V40 Guides, News, & Discussion] qpfmj95o:
Could anyone provide me with the stock android 10 able file? The pie file won't work
[LG V40 Guides, News, & Discussion] AsItLies:
yer gonna need the boot+twrp image of your boot loader. It's version specific, so which version of 10? 10c? 10d? 10e? etc etc.

they are not interchangeable.
[LG V40 Guides, News, & Discussion] AsItLies:
stock 10? att? sprint? vzw? korean? And stock 10 what? 10c? 10d? 10e?
[LG V40 Guides, News, & Discussion] qpfmj95o:
Att android 10 my fault
[LG V40 Guides, News, & Discussion] qpfmj95o:
Att 10e my fault
[LG V40 Guides, News, & Discussion] AsItLies:
good. This is the link with att 10e patched with twrp boot partition.

keep in mind, you have to flash this to current boot partition with either qfil or fastboot.

Then, go directly to recovery, do not boot device.

1) format data (not wipe).

2) reboot recovery

3) flash magisk

4) flash dm-verity

should be all set then.

cheers
[LG V40 Guides, News, & Discussion] qpfmj95o:
Thanks man I will try
[LG V40 Guides, News, & Discussion] min41rpa:
Please help!

My phone now stuck at the fastboot

It shows PRODUCT_Name - LM-V4059N and when I tried to boot the rom, the yellow triangle appears.
[LG V40 Guides, News, & Discussion] AsItLies:
It sounds like your device switched slots? Or maybe you flashed to both slots and are trying to boot the phone with the eng abl flashed?

It's important to realize, as the guide says, the eng abl is Oreo. It will not boot any other OS but Oreo. It's only to be used to unlock the BL and then flash the original abl back, so the phone can boot.

cheers
[LG V40 Guides, News, & Discussion] min41rpa:
I flashed in slot a, at fastboot it shows slot a active too. I'm already flashed back to Pie abl and it stucks at fastboot, 1 more thing, when i use the code flash oem unlock the second time, cmd shows FAILED (remote: unknow command)
[LG V40 Guides, News, & Discussion] AsItLies:
sounds like kind of a mess. Which model is your phone originally? Vzw? att? Kor?

So if yer flashed back to original pie abl... how do u still have fastboot? are you getting to the fastboot screen using pwr+vol up? You're getting to fastboot just by booting phone?

and, the command to unlock bootloader isn't 'fastboot flash ...' it's just 'fastboot oem unlock'. The command 'flash' is for flashing a partition. The 'oem unlock' doesn't flash anything.

cheers
[LG V40 Guides, News, & Discussion] min41rpa:
My model is Korea KT V409N, sorry for my typing mistake sir :(

I'm already flash back to pie by kdz and the bootloader was unlocked but I can't access to fastboot by cmd nor button.

Gosh, this phone so hard to install twrp :(

Any solution for this? Thanks, have a great day.
[LG V40 Guides, News, & Discussion] Xenjira:
Has anyone made a full video guide of this process , i cant seem to find one ,

If anyone be willing that be awesome
[LG V40 Guides, News, & Discussion] AsItLies:
Is it korean open? as in KOR? Or is it KTF? I think that's korean carrier specific...

anyway, this guide shows how to flash the v35 eng abl so that you'll have fastboot. The v35 eng abl is Oreo, the phone won't boot with it installed, unless the OS is Oreo.

Did you follow this guide and unlock the bootloader? I ask because if u did, you'd know how to get fastboot, but it doesn't sound like you do?

There's another way to get a 'watered down' version of fastboot, by nuking the laf partition (that's needed to use lgup though). But the korean versions (at least the Open version), the fastboot you get (nuked laf) is very minimal, it does almost nothing.

There's another guide showing twrp, check that out also.
[LG V40 Guides, News, & Discussion] Mitno:
Im done with the sahara error...
[LG V40 Guides, News, & Discussion] anh102w:
Could you give me the file of 409N 30f?
[LG V40 Guides, News, & Discussion] AsItLies:
sure this is it.

remember, flash this with qfil or fastboot to the current boot slot. After flashing, go immediately to recovery, don't boot phone.

1) if it asks for password just cancel

2) format (not wipe) data

3) reboot recovery

4) flash magisk

5) flash dmverity

should be all set then.
[LG V40 Guides, News, & Discussion] anh102w:
So sorry, I'm a bit nervous. Replace this file here, right?
[LG V40 Guides, News, & Discussion] anh102w:
I'm sorry, but I stuck in Fastboot, even after flashing boot_a, then reboot to recovery mode, then factory reset. It cannot boot into twrp.
[LG V40 Guides, News, & Discussion] anh102w:
Ah, after all, I can go into TWRP by flashing boot_b and reboot recovery. Thanks a lot!!!!!
[LG V40 Guides, News, & Discussion] athoti:
My phone is LM-V405UA software version V405UAg. I followed the steps and bootloader shows unlocked but I can't flash TWRP. My error is 'Cannot flash this partition in unlocked state' Of all the steps, I missed "fastboot flash frp path/to/frp" but went straight to "fastboot oem unlock" and it did unlock it, shows it in fastboot. I also couldn't "fastboot flash abl_a path/to/ablpiestock.img" so flashed it via QFIL -> abl_a. Would someone know what could possibly be the issue? I've gone back and forth between reflashing V35engineering, deleting laf_a and laf_b, rewriting them (thanks to someone who provided them here) etc. but nothing works. My goal is LineageOS. Many thanks!
[LG V40 Guides, News, & Discussion] AsItLies:
Sounds like there's some confusion re fastboot.

There are 2 ways to get fastboot on the device. 1 way results in full blown fastboot (v35 eng abl - can unlock bootloader), but it's Oreo based. The other way is to 'erase laf' partition, but it's a watered down version of fastboot (can't unlock bootloader).

And the 'frp partition' flashing is only needed if you're on Verizon, as the instructions say. If you're not on Verizon, then you simply go to developer options and enable 'OEM unock' (Verizon doesn't have that option).

Depending on the version of Android, the newer ones, which you *probably* have, you don't flash twrp anymore, you have to have your specific boot partition with twrp injected into it (then you flash that specific boot partition).

And lastly, your software version is something like Korean Open 30f, or maybe US OPEN 20e, or maybe AT&T 30d, etc etc. You have to know the exact info for anyone to be able to help.

cheers
[LG V40 Guides, News, & Discussion] athoti:
Thank-you much for helping out!

I don't know, software version says V405U20g and it starts with a splashing Sprint sign... Kernel 4.9.112. The phone I bought "new" off ebay.

How do I do this?
[LG V40 Guides, News, & Discussion] AsItLies:
So you're on Sprint 20g, which is Android Pie. First (and always) you need to use qfil to backup any partitions you plan on modifying. You say 'someone here provided laf backup' that you used to restore, but that's a prob because Sprint doesn't make their kdz available and I've not seen any backups for the Sprint firmware... so what laf backup did you use?

And, as I explained, there are 2 versions of fastboot; 1) v35 eng abl and 2) laf nuked (watered down) version of fastboot.

I've no experience with the Sprint (watered down) version of (laf nuked) fastboot, but it seems to be like other mfg versions, in that it won't flash a partition. So, you have to use the v35 eng abl fastboot to do that.

Unfortunately, the v35 eng abl won't 'boot' a partition unless it's Oreo. You'll have to use qfil and save your boot partition (a or b), and post it here. I'll inject twrp into it for you and post it back, then use qfil to put it back.

cheers
[LG V40 Guides, News, & Discussion] Gorbieee:
Any ideas why my phone refuses to show up under the Qualcomm HS-USB QDLoader 9008 port? I can only get it listed as LGE AndroidNet USB Serial Port. I believe the bootloader is currently unlocked but I'm feeling like I'm missing something on my pc for the connection. I've attempted to follow the resolutions in this thread but no luck so far. Obviously doesnt show up under the QFIL port menu, it does appear when the "Show Non QDLoader\DIAG Port" checkbox is selected, but still under the LGE AndroidNet USB Serial Port name.

Realize I should have included this information:

Model: LM-V405UA

Android Version: 9

Kernel Version: 4.9.112

Downloaded latest version of QPST (latest I found was 2.7.480) and I also have the LG Mobile Driver WHQL version 4.2.0.
[LG V40 Guides, News, & Discussion] AsItLies:
I'd suggest use this driver, it is signed and should work without issues. In my experience one of the big issues is Windows and it not allowing unsigned drivers. There are ways around it, depending on win version, but all of them are a pain to do.

also, be sure to use a usb 2.0 port, not 3.0. Qfil is older software, designed prior to more modern hardware. When I've accidentally used a usb 3.0 port, I've had flashing and backups fail due to corruption.

cheers
[LG V40 Guides, News, & Discussion] athoti:
Do you keep POWER + VOLUME DOWN pressed together, then release them and rapidly press volume up as soon as the screen goes blank? Or even a split second before. You may have to try a number of times. You can do it (pressing the buttons) from Fastboot or Download mode too.

Also I had to restart my computer before it worked. Now it works every time no problem. I tried both USB 2.0 and 3.0 but it didn't make a difference.

If the bootloader is unlocked it should show at startup a yellow triangle with "your device cannot be checked for corruption bla bla bla"
[LG V40 Guides, News, & Discussion] athoti:
I got the laf_a and laf_b that ngowner provided here on page 12. I see they are 20e pie but they've worked for me. I went between flashing v35 eng. and deleted laf-a and b and reflashing them a number of times to try to flash twrp but no success. You're right I have fastboot when I delete them but then I can't flash anything because they're deleted ...

Here are the boot partitions. I hope I did it right? I'm not experienced with QFIL. So I went to tools -> partition manager -> boot_a -> read. Is that the way?

Thanks again!
[LG V40 Guides, News, & Discussion] Gorbieee:
Absolutely love how fast the response time is on here (not sarcasm). I managed to get the phone into 9008 mode, boy that timing is precise. Its showing up in my ports under Qualcomm HS-USB QDLoader9008 as its supposed to.

Now my main issue is that I'm unable to get past a sahara error in QFIL. I get error 277 unable to read packet header, only read 0 bytes.

This is when trying to open the partition manager. I selected the options to match as best as I could. I cant seem to find the "rawprogram0.xml" file anywhere but I wasn't sure if that was required just to access the partition manager.
[LG V40 Guides, News, & Discussion] athoti:
Yes I know, I've been helped at times too and very quickly. I'm definitely not a pro, only have flashed some things here and there :) but I'll try to help if I can and hopefully I don't mess things up.

All I can say is I had the "sahara error" many a times until I restarted my computer, checked for update driver in windows device manager and then it worked. At some point I had QFIL opened on one side of the screen with my mouse on Tools -> Partition manager to select that as soon as I entered phone in 9008 but I'm not sure it helped or not. Now as soon as it goes in 9008 mode I can take my jolly time, there's no need to hurry anything.

You only need to select Storage Type on the bottom: ufs, then SelectPort -> your 9008 port and select programmer -> the "prog_ufs_firehose_Sdm845_lge" file (that I placed in a folder directly on C drive and there again not sure if that was what did it) You don't need to select the flat build.

Hope it helps something.
[LG V40 Guides, News, & Discussion] Gorbieee:
Currently out, will try reboot when I get home. Port selection should be fine. The flat build auto populates when is elect that firehose file. Do I need the rawprogram0.xml file? If so where would I get that?

Edit: Tried reboot, no luck. Phone is currently in 9008 mode, disconnected and as soon as I connected it I tried to open the partition manager, same error. Attaching QFIL image for clarity.
[LG V40 Guides, News, & Discussion] AsItLies:
No, you don't need the rawprogram xml file(s), those would be needed when restoring a backup. It was really an oversight that it was on the original screens when making the guide.

it's not needed. Cheers