Develop Bugs

LG G3 not being recognised, USB not transferring files

I'm hoping someone can help. I have an LG G3 D855 phone and is factory unlocked and running Lollipop 5.0. When I first got the phone (second hand), I was able to connect the phone via USB to my PC and was able to transfer files back and fore no problem. Until about 3 weeks ago, I am now unable to do this. The PC won't recognise the phone at all, all the USB connection does is charge the phone and I can see no option to get the phone to change to file transfer mode.
I had a look at Storage in the settings menu and I don't have the three dots that some people have spoke about. I have factory reset the phone and this hasn't fixed it.
I have tried using a different USB cable, this was the same. The drivers are installed (phone was recognized before). I have also tried the LG Suite, again same result. I also had a look in Device Manager for ACER something or other and this wasn't there.
I am currently having to use Bluetooth to transfer files back and fore to my PC and this is a bit slow. I'm assuming that an update LG have done has somehow broke the USB settings. I am also unable to root the phone (tried this before the USB stopped working and nothing worked) and possibly go back to KitKat 4.4.2 to even try that.
My phone has software version V20u-EUR-XX, Kernel Version 3.4.0 and build number LRX21R.A1439960697. There is no update available for my phone in the Software Update center.
After quite a bit of searching, it seems that this is a common issue but I have not found a solution to this. Can anyone help? Is there any firmware or software that I can try?
Thanks.

Assuming the OS is Win8/8.1 or Win10, have you already tried this?...
[How to fix] Windows 8/8.1/10 is not detecting my LG G3 device
http://forum.xda-developers.com/lg-g3/help/answer-windows-8-8-1-detecting-lollipop-t2967574/post57373374#post57373374
... or tried the suggestions in this thread?: http://forum.xda-developers.com/lg-g3/help/lost-usb-connection-mode-t2847857

Thanks for the reply. I am using Windows 7 Home Edition 64 Bit and had had a look for the ACER Composite ADB Interface in Device Manager and it wasn't there. Post #18 in the thread you linked to, I have no idea what kdz file I would need. Does this method need the USB to working?
Thanks for the reply and help.

I have D85520T_00.kdz and D85520U_00.kdz files. Can someone tell me if these are OK for my phone (and latest) and what the differences between the two are (apart from the file names?) Thanks again.

I couldn't tell you what the differences are between software revisions, only that 20u is newer. And I believe 20w is the latest available. I would probably try reinstalling the latest drivers from LG...
http://www.lg.com/us/support/software-firmware
... then again check to see if your PC recognizes the phone. If the "Charge phone--> Tap for more USB options" notification doesn't appear after installing the latest driverset, I'm not sure what else you could try. The LG Flash Tool needs to be able to communicate w/ the device when it's in Download Mode. You might be able to find something in the [Guide] LG G3 Stock Firmware (Go Back to Stock) KDZ & TOT Method thread related to the same problem you're having.
http://forum.xda-developers.com/showthread.php?t=2785089

Just a quick update, can't even get the phone into download mode. I press volume up, insert the USB cable in to the PC and all I get is the battery charging icon. I'll have a further look this weekend - not good so far!
Thanks again for the replies and help.
Firmware W seems to be flashable only via TWRP or ClockWorkMod just now?

I have been able to get the phone into Download Mode a few times (not all of the time) and when I run LG Flash Tool, it just tells me that the phone isn't connected. I'm going to assume that the USB port is in someway defective. Can't think of anything else.

Have you tried w/ a different PC and/or OS? Have you tried connecting the phone via different USB ports (USB 2.0 compared to USB 3.0 or vice-versa)? And I assume you've already installed the latest driverset from LG?...
http://www.lg.com/us/support/software-firmware

Yes, I got into Download Mode once or twice on the laptop. I'm using LGMobileDriver_WHQL_Ver_4.0.3. I have tried USB 2 ports on both my Laptop & PC. I've tried driver 3.81 as well.

OK, got a new USB Charger port fitted just in case it was the port that was wrong and it's still exactly the same! I did a factory reset and have setup the phone for now. During the factory reset, it does pop up with Updating Android and has 169 updates. If anyone here has the LG G3 and has it working file transfer wise, can you tell me what version of the LG USB drivers you are using? Is it possible an LG update has caused this?
Thanks.

It's fixed!!! I think there was an update yesterday for Android Devices or Services, can't remember which was made available yesterday, installed that, reconnected the phone to the computer just a few minutes ago and it has finally been recognised! I can finally transfer files between the phone and the PC.
It was an LG update that has fixed this.
At last.
I'd like to say thank you for all the replies and help.

[H811] ADB Broken after Rooting?

Yesterday I decided to install ClockworkMod. I was running 6.0.0 Marshmallow
I unlocked my bootloader no problem. I decided to root before I flashed the rom. I booted into TWRP using adb, made a nandroid backup, and flashed stock-20a-rooted.zip (I was following this guide). It worked! I used a rootchecker app to ensure I had a good root. Then I went to boot into TWRP to install ClockworkMod. I turned off my phone and did the volume down + power thing, but I got the LG hard factory reset screen. So I decided to use ADB instead and rebooted my phone. However, when I tried to use adb, my device was listed as "unauthorized", and I haven't been able to use adb since! Here's what I tried (but not necessarily in this order):
Using the LG hard factory reset. Nothing changed.
clearing adbkey file on my computer. Nothing changed.
using a different computer with fresh adb and driver install. Nothing changed.
rebooting both PCs. No dice.
tried mtp and ptp on device. Neither worked. Device was not recognized on MTP (used to be recognized by adb when it was on mtp.) device was recognized on ptp, but it was listed as "unauthorized"
tried to revoke usb debugging in settings on device. That option wasn't listed in developer options.
tried to clear adbkey on device and found out that my device still hadn't generated an adbkey file!
throughout this whole time, whenever I plugged in my device, the NSA fingerprint dialog box DID NOT APPEAR.
Questions, thoughts on potential solutions:
can I somehow unroot or go back to stock? I heard we can't do this anymore because it bricks our phones....
I feel like this has something to do with how my device never created an adbkeys file.

SOLUTION
I have been working on this today and I found a solution. I had read that downgrading/unrooting bricks our devices, and so I had ruled it out as an option. After further research I found that we can revert to stock without downgrading and avoid a brick. Since I have an H811 on 20o, I found firmware here and flashed it using LGUP, which you can find here. I suggest using this link to learn how to flash the firmware. After that, ADB worked fine and the NSA fingerprint dialog once again showed up on my device when I ran ADB. Good luck to any of you with the same problem!!! Reply if you need help.

Bricked LG G Pad 8.3 - Computer does not recognize the device

Hi all,
This is my first thread on this website and I am not that expert of rooting and installing custom ROM's. I am trying to find a solution on your website for 2 days but I couldn't solved although I tried everything.
I have an issue with my LG G Pad 8.3 (LG V500) tablet. It was installed 5.0.2 stock ROM (Korean version) and I decided to root the device and install custom ROM. I used King Root to unlock the device. Then I installed TWRP thing to my tablet and started flashing ROM process. While working the tablet restarted automatically and it was stuck at the startup with a LG icon on the screen.
I decided to make factory hard reset it in order to get rid of this but when I try to make factory reset with button combinations I get the following error;
* Confirmed *
Secure booting Error!
Cause : boot certification verify
Then I searched for the forums and first installed Android Studio, then by using SDK manager tools, I also installed USB drivers.
As the device can connect download mode, I installed adb thing and tried to fix it. But apparently laptop does not recognize the device. I run the command "adb devices" and there is no devices in the list.
I also tried to use twrp recovery tools but again it didn't recognize the device.
When I check the Device Manager when the tablet is connected to laptop on download mode, I can see LGE AndroidNet USB Serial Port (COM4) thing installed. I also tried to install Android Device drivers (Android ADB Interface, Android Bootloader Interface, Android Composite ADB Interface) but they are not working properly and they have question mark on their left side.
So as you can understand I am drawning with the issues and don't know what to do next. Apparently laptop does not recognize the device but although I checked the xda forums and other forums for 2 days, I couldn't solve. I would really appreciate if you can help me.
Best

ironunited said:
Hi all,
This is my first thread on this website and I am not that expert of rooting and installing custom ROM's. I am trying to find a solution on your website for 2 days but I couldn't solved although I tried everything.
I have an issue with my LG G Pad 8.3 (LG V500) tablet. It was installed 5.0.2 stock ROM (Korean version) and I decided to root the device and install custom ROM. I used King Root to unlock the device. Then I installed TWRP thing to my tablet and started flashing ROM process. While working the tablet restarted automatically and it was stuck at the startup with a LG icon on the screen.
I decided to make factory hard reset it in order to get rid of this but when I try to make factory reset with button combinations I get the following error;
* Confirmed *
Secure booting Error!
Cause : boot certification verify
Then I searched for the forums and first installed Android Studio, then by using SDK manager tools, I also installed USB drivers.
As the device can connect download mode, I installed adb thing and tried to fix it. But apparently laptop does not recognize the device. I run the command "adb devices" and there is no devices in the list.
I also tried to use twrp recovery tools but again it didn't recognize the device.
When I check the Device Manager when the tablet is connected to laptop on download mode, I can see LGE AndroidNet USB Serial Port (COM4) thing installed. I also tried to install Android Device drivers (Android ADB Interface, Android Bootloader Interface, Android Composite ADB Interface) but they are not working properly and they have question mark on their left side.
So as you can understand I am drawning with the issues and don't know what to do next. Apparently laptop does not recognize the device but although I checked the xda forums and other forums for 2 days, I couldn't solve. I would really appreciate if you can help me.
Best
Click to expand...
Click to collapse
I couldn't get the computer to recognize one of my LG devices using ADB until I used this...http://forum.xda-developers.com/showthread.php?t=2588979

unable to boot despite flashing multiple OEM KDZ files, soft brick?

I have a LG G3 D855 I've been looking at for about a week now, it wont boot no matter what is flashed onto it. Tried as many guides as I could find but still nothing.
Anyone got any ideas?
Tried Flash tool with KDZ direct from LG, tried installing TWRP but it won't install, tried LG PC suit recovery and nothing. na-da.

jettonx said:
I have a LG G3 D855 I've been looking at for about a week now, it wont boot no matter what is flashed onto it. Tried as many guides as I could find but still nothing.
Anyone got any ideas?
Tried Flash tool with KDZ direct from LG, tried installing TWRP but it won't install, tried LG PC suit recovery and nothing. na-da.
Click to expand...
Click to collapse
Is it recognized in the device manager of your PC? If yes - what does it say?
*When I'm in download mode it shows up as "LGE Mobile USB composite device" under USB controllers.

startswithPendswithOOH said:
Is it recognized in the device manager of your PC? If yes - what does it say?
*When I'm in download mode it shows up as "LGE Mobile USB composite device" under USB controllers.
Click to expand...
Click to collapse
Yep that's exactly what this one shows up as.
I can boot into download and I can boot into stock recovery mode.
gyazo.com/1a09d74b4ae3a04d6587eb9096438ffc

jettonx said:
Yep that's exactly what this one shows up as.
I can boot into download and I can boot into stock recovery mode.
gyazo.com/1a09d74b4ae3a04d6587eb9096438ffc
Click to expand...
Click to collapse
Actually...it's not what it's showing up as. Under "Universal Serial Bus controllers" it should be listed, but yours is listed as LGE AndroidNet USB serial port(com 41) under "ports". That is looking like a soft brick. I had a similar problem occur when I unplugged a phone while it was flashing/upgrading. You'll need to TOT back to stock since KDZ has failed you. Scroll down to the TOT method... https://forum.xda-developers.com/showthread.php?t=2785089
I see you are on com41 - have you already tried TOT? If yes and it fails, what is the error?
*Also, you may need to uninstall any mobile device drivers and reinstall just the LG drivers for things to work right.

startswithPendswithOOH said:
Actually...it's not what it's showing up as. Under "Universal Serial Bus controllers" it should be listed, but yours is listed as LGE AndroidNet USB serial port(com 41) under "ports". That is looking like a soft brick. I had a similar problem occur when I unplugged a phone while it was flashing/upgrading. You'll need to TOT back to stock since KDZ has failed you. Scroll down to the TOT method... https://forum.xda-developers.com/showthread.php?t=2785089
I see you are on com41 - have you already tried TOT? If yes and it fails, what is the error?
*Also, you may need to uninstall any mobile device drivers and reinstall just the LG drivers for things to work right.
Click to expand...
Click to collapse
The TOT went on fine but it still won't boot, it's a strange one this phone..

Help usb and fastboot not reconized

I am getting a Unknown usb device (device descriptor request failed) It keep telling me usb device not recognized while being plugged it. I have tried several things
1. another windows 10 computer worked the first time then same error as a laptop.
2. unintalled the driver and rebooted.
3. also used multiple usb ports
cant find anything after searching
pixel 2 xl 8.0 September update
rooted lastest magisk 15.3
latest twrp installed
stock kernel
recently a fresh install a few days ago because i got it to work somehow but not anymore what do i do?
adb, fastboot, and storage cannot be accessed

Try these steps:
-uninstall previous version of SDK tools from PC
-download latest SDK Tools from HERE
-have a USB 2.0 cable available
-follow these steps to verify connectivity
see if these things help
Unless there is a specific reason you're still on Sept 8.0, I'd take this chance and upgrade to lasts 8.1 factory image.

evanxalmighty said:
I am getting a Unknown usb device (device descriptor request failed) It keep telling me usb device not recognized while being plugged it. I have tried several things
1. another windows 10 computer worked the first time then same error as a laptop.
2. unintalled the driver and rebooted.
3. also used multiple usb ports
cant find anything after searching
pixel 2 xl 8.0 September update
rooted lastest magisk 15.3
latest twrp installed
stock kernel
recently a fresh install a few days ago because i got it to work somehow but not anymore what do i do?
adb, fastboot, and storage cannot be accessed
Click to expand...
Click to collapse
I'm just spitballing here but....
With phone plugged in, on your pc, under device manage. When you open it up do you see unknown android device? That driver may need to be updated. Also, USB debugging is on, and the option to transfer files? Is your SDK platform-tools up to date?

I forgot to mention downloaded the platform tool for both computers. I never updated because i had root and nothing new was that interested enough to start all over. I followed the steps and nothing usb debugging is on. In device manager its says Unknown usb device (device descriptor request failed). I cant transfer files or anything. I tried updating to the google driver but it said it wasnt compatible.

I haven't seen it with this phone yet, but try changing the USB mode on your phone from the notification; I've had a few phones that refuse to work in specific modes.

evanxalmighty said:
I forgot to mention downloaded the platform tool for both computers. I never updated because i had root and nothing new was that interested enough to start all over. I followed the steps and nothing usb debugging is on. In device manager its says Unknown usb device (device descriptor request failed). I cant transfer files or anything. I tried updating to the google driver but it said it wasnt compatible.
Click to expand...
Click to collapse
Have you tried a different USB-C-A cable just for the heck of it. May have to factory reset and see if that solves it.

evanxalmighty said:
I forgot to mention downloaded the platform tool for both computers. I never updated because i had root and nothing new was that interested enough to start all over. I followed the steps and nothing usb debugging is on. In device manager its says Unknown usb device (device descriptor request failed). I cant transfer files or anything. I tried updating to the google driver but it said it wasnt compatible.
Click to expand...
Click to collapse
So your driver is messed up. Did you use the driver below?
https://dl-ssl.google.com//android/repository/latest_usb_driver_windows.zip
Sent from my taimen using XDA Labs

It won't let me install the driver I get some kind of error when selecting it. I was able to get it to work after plugging it in and out. Now that I updated to 8.1 everything was fine untill I got home. Now it's doing it again. I tried 2 different cables restarted my computer and laptop and can't figure out why it was working fine before without doing anything different.

Try this:
1. Go to C:\Windows\INF
2. Find the file "wpdmtp.inf"
3. Right click the file and click 'Install'
4. Once that is done, simply plug your phone and it should work.

JimSmith94 said:
Try this:
1. Go to C:\Windows\INF
2. Find the file "wpdmtp.inf"
3. Right click the file and click 'Install'
4. Once that is done, simply plug your phone and it should work.
Click to expand...
Click to collapse
This definitely worked for me -- Thanks for posting!

I am having sort of the same problem. I was on Android 11 on my 2xl, rooted with fast boot boot twrp.Img and installed magisk and super super, all latest. I could not get gaps so I used Android flash tool to attempt to go back stock and it downloaded and flashed it but it is now stuck in loop, I reboot to recovery and it’s stock now and it will not be recognized by adb or fast boot,!0plesase help