Unless you bought the LG G3 before a certain date, you most likely have a version of Android that can no longer be rooted. So today I wanted to take you through the step by step guide on how to downgrade your LG G3 so you can root it.

When a new device comes out the hackers and coders dive in and try to find an exploit. It’s this exploit that allows us to gain root access, which allows us to unlock the bootloader, which allows us to install a custom recovery, which allows us to install a custom ROM. As these exploits become public, the Android OEMs usually try to patch that exploit as soon as possible.

The hackers can either try to find another security hole to exploit or the community can come up with a way to downgrade. This is what I’m going to show you today.

Since most of the LG G3 smartphones that are sold today are running a version of Android that is no longer exploitable, I’m going to show you how to downgrade your LG G3 back to an older version of Android. Once you have downgraded to an earlier version of the Android firmware, you can then use the root tool that the community has been using for a while. I do not have a list of which versions of the LG G3 firmware is rootable or not. If you are a new owner of an LG G3 then I suggest you check out the how to root the LG G3 article and see if you can gain root access to it.

If you cannot get into the LG G3 with Stump then you’ll want to follow this guide on how to downgrade. This tutorial is actually very similar to the how to revert the LG G3 to stock article that I wrote about not too long ago. The premise is the same though, we’re just going back to an older version of the firmware and this just happens to be the stock LG G3 firmware too. Once you go back to an older version of the Android firmware, you can root it, unlock it and then install a newer version of Android.

Downgrading your version of Android is essentially like a factory reset. You will lose all of your data and it will be like you had just pulled the phone out of the box brand new.

Downgrade LG G3

  1. Power Off the LG G3
  2. Plug in a Micro USB Cable into Your Computer
  3. Press and Hold the Volume Up Button on the LG G3
  4. Plug in a Micro USB Cable While Still Holding the Volume Up Button
  5. Wait Until You See a Firmware Update Screen
  6. Let Go of the Volume Up Button
  7. Press the Windows Key on Your Keyboard
  8. Search for Device Manager and Open it
  9. Locate the COM & LPT Ports Option and Expand it
  10. Make Sure You See LGE Mobile USB Serial Port
  11. If You Can’t, Download the LG USB Drivers and Install Them(and then restart your PC)
  12. Double Click LGE Mobile USB Serial Port
  13. Click Port Settings
  14. Click Advanced
  15. Change the COM Port Number to COM41
  16. Click OK and then Click OK Again
  17. Download LG FlashTool
  18. Extract LG FlashTool and Install
  19. Do Not Run LG FlashTool When it Finishes Installing
  20. Navigate to the Extracted LG FlashTool Folder
  21. Copy and Paste the MegaLock.dll File to C:\LG\LGFlashTool (assuming that is where you installed it)
  22. Download the Stock Firmware for Your Specific LG G3 Model
  23. Extract the Stock Firmware File to Your Desktop
  24. Open LG FlashTool
  25. Click on Manual Mode
  26. Click the “…” Button at the Top Right
  27. Locate the .DLL File from the Firmware Download Page
  28. Click Add
  29. Locate the .TOT File from the Extracted Firmware Folder
  30. Click OK
  31. Click the Yellow Arrow at the Top Left
  32. Wait Until the Gray Box in the Middle Disappears
  33. When You Have One Yellow Box that Says Ready(all other boxes say disabled)
  34. Unplug the Micro USB Cable from the LG G3
  35. Plug in the Micro USB Cable Back into the LG G3
  36. Let LG FlashTool do its Thing
  37. After ~5 Minutes the LG Flash Tool Should Say “PASS!!”
  38. If You Have a Blue Screen on Your LG G3, This is Good
  39. Blue Screen Should Say “Factory Reset Status” with the Number 3
  40. Unplug the Micro USB Cable from the LG G3
  41. Remove the Battery and then Replace it
  42. Power the LG G3 Up
  43. You Should See the LG G3 Boot to the Setup Screen
  44. This Means You are Back to the Stock Firmware with No Root

Note – I am getting feedback from Reddit user /u/codytheking and he is telling me that he had to change his Action Mode option(in LG FlashTool) from ‘Upgrade DL’ to ‘Board DL'(right before step 30). If I could get more people to give me feedback on this option to help confirm or deny this then I will add it into the tutorial if needed.

I’m also getting feedback that this should be performed with a USB 2.0 port. If you are trying this with a USB 3.0 port then you will most likely get errors(although, I just received a comment saying that they were able to get it working with USB 3.0). Remember, you should be using the original USB Cable cable that came with the LG G3 as generic ones can give you errors as well

Another user wanted me to warn you that between steps 36 and 39 that “your phone may do some weird things, be patient and wait for the blue screen” 🙂

More feedback has come in from a T-Mobile user who says “I tried this method again and after downgrading I was stuck with the same problem (Sim card not working). While my phone was still in the initial set up mode (sim card not working) I plugged my phone back into my computer. Almost instantly the sim card started working and I am now fully connected to T-mobiles 4g LTE network”. So you might want to try this in case you run into the same issue.


The first thing we need to do is to get your LG G3 into Download Mode. Getting into Download Mode on the LG G3 allows us to install a fresh firmware onto the device with the LG FlashTool program. In step 22 I link you to a list of stock firmwares for the LG G3 courtesy of Android Rootz. When you visit that page, scroll down to the bottom and download the one that matches the model of your LG G3. Since I have the AT&T LG G3, I would click the D850 link and download both the zip file and the dll file that is listed on that page.

The rest of this tutorial is basically just setting up LG FlashTool properly. It can be confusing at first but you quickly start to get used to it. Since you’re following along with this tutorial step by step, it shouldn’t be too difficult. As always, if you have any questions then scroll down to the bottom of this article and leave a comment. I will always try my best to help everyone that I can. If something in the tutorial doesn’t match up properly with what you are doing then it is better to ask than to guess.

Once you have installed the original firmware file for the LG G3 onto your device, then you can follow the guide on how to root the LG G3. Once you are rooted you can follow the guide on how to unlock the LG G3. Unlocking the bootloader of the LG G3 will install a custom recovery(TWRP) and this is where you can perform your first Nandroid backup. It is always recommended that you backup your device before you start to install any custom ROMs, custom kernels, or modifications that require root access.

If you get the error Factory Status 2, maybe this tip will help you get through it.


  1. I only made it to #2 on the blue screen then it said failed and open usb…. restarting only goes back to blue screen. Help!!

  2. I just flashed mine (D855 / 32Gb) and did not have to change to ‘Board DL’. Everything is working fine, thanks for the effort.

  3. for some reason i just cant get it to click in my head but how do you do step 21? Just cant think straight.

  4. I got as far as step 37, but after 5 minutes it hadn’t done anything. On the phones screen it said something about screen calibration and Do Not Touch Screen! Underneath this it had an OK button…. I wasn’t sure what to do but after it sat there for an hour I shut down the Flash Tool cos I thought it had got stuck and I tried to run it again…. then I thiought perhaps I should have pressed OK, tried it and it ran through a calibration. I never got to see a blue screen or to see the Flash Tool PASS message. Despite having disconnected it by that point, it still seems to have worked and now it’s operating fully and ok as far as i’m aware, on the new downgrade.

    P.S. I also had to change my Action Mode option (in LG FlashTool) from ‘Upgrade DL’ to ‘Board DL'(right before step 30) to get anything out of it. Previously it just did nothing.

  5. thank you thank you!!
    i was trying to go back to kitkat for a while, i’m not completely satisfied with many things in lollipop, and now i can root my G3,
    again, thanks!!!!

  6. STEP 27 – Locate the .DLL File from the Extracted Firmware Folder
    There’s only tot file in the firmware (D855 Hong kong 16gb). No DLL. what should I do to continue?

  7. Worked like a charm. Using usb 3.0 and original cable. (model D855 32GB) Flash tool showed download fail, but phones screen said like it should have. So I booted up my phone like in instructions, and I was successfully downgraded. Thanks!

  8. I’ve used this method before to remove Stump root from my phone to allow me to update from Kit Kat to Lollipop. Unfortunately there are issues with audio/bluetooth under Lollipop so I was hoping to flash Kit Kat 4.4.4, re-root and then flash CyanogenMod 12. I’ve ran into a problem though. As I’ve said, I’ve done this before so have all the drivers/programs installed. I get to the stage where Flashtool says ready but when I disconnect the USB and re-insert nothing happens. I’ve tried using board instead of upgrade too.
    I have noticed in Device Manager though that when plugged in my phone appears under Portable devices as LG G3 phone but there is a yellow triangle with an exclamation mark in it, suggesting a driver issue but I’ve installed, and re-installed drivers for it. I’ve installed them manually and let Windows choose automatically. Any suggestions?

    • You definitely need to use the drivers from LG’s website. Letting Windows install them for you probably isn’t going to allow it to work properly.

      Have you right clicked it and uninstalled it? Then installed the LG drivers? If I had to guess, I would think that it has something to do with the drivers(which is why you’re seeing an exclamation mark). Maybe a reboot of the PC after installing the drivers might help

      Are you on Windows 8? I found this


      This person was able to get past it by using a different PC, so again, it seems to be an issue with the drivers/detection of the G3 and the PC. Someone suggests disabling signature verification. I’m not sure if that will help though since it didn’t help the OP there. It might be worth testing though

    • I think this guide will only help you if you are on Windows. I don’t run a Mac so I can’t speak from experience though. If someone else here reads this and can help, maybe they will reply and let you know

  9. Im thinking of trying this out today. I updated to android 5.0 and i hate it. Will this erase all my apps and music e.t.c??

  10. I keep getting a FAIL at “Change to DL Mode”. I’m on Windows 8, installed drivers directly from LG and using the stock LG USB cable. I tried using the “Upgrade DL” and “Board DL” in setup.

  11. Hello im having trouble finding the correct stock firmware to download? i bought mine in Singapore so im not sure which one to use? All i know is that its d855

  12. After a few tries it finally worked.

    The “Factory Reset Status” originally got stuck at 2, so I tried with Action Mode “Board DL”. That didn’t work either. Third time was the charm reverting to “Upgrade DL”.

    I have a Macbook, so I used a Windows 7 virtual machine with Virtualbox. The Macbook has USB3 ports, but the Virtualbox only allows for USB2. I don’t know what prevails in that situation, but it worked for me.

  13. My device still has its warranty unfortunately i updated it to lollipop and i don’t like it that much due to battery issues. Does this need to have root access? (sorry new here)

      • If you’re having battery issues with Lollipop, and that’s the only thing that is happening, I would suggest a factory reset before you try downgrading. A factory reset will fix most of the random bugs, issues and glitches that crop up due to a new update

    • No, you do not need root access in order to downgrade with this guide. This guide is actually loading up the older firmware(KitKat in this case) with a tool called LG FlashTool and it does so by booting into Download Mode. Getting into download mode opens up the window for downgrading and does not require root access.

  14. I just flashed my G3 from 12b to 10b using your instructions, on a Win 8.1 PC.

    In my attempt to flash it, between steps 36 & 37 the flash tool changed to red and displayed “Download Failed”, and at that point the G3 decided to only boot into “Mini OS” and display a testing screen. This was using the “Board DL” option.

    I had a small panic attack, and then tried again, but changed the flash tool to “Upgrade DL” this time.

    It worked just fine, and I’m now back to the original firmware.

    Thanks for the instructions.

    • Thank you for the detailed feedback and I’m glad you were able to get it working by changing that one setting.

      Hopefully if anyone else gets this error then they will try what you did and be able to fix it

    • OMG! I know this post is old, but I just had the need for it these last couple of weeks. I had upgraded to the Android Marshmallow OS and wanted to revert back to KitKat. I have the VS985 Verizon LG. This post was very helpful. The instructions above are great. One of the most important lessons I learned after at least 30 hours of trial and error was that I HAD TO USE THE OEM USB cable. I had to order one from Amazon and wait for it to come in. I first ran the entire process in UPGRADE DL, which got me stuck in Factory Reset 2 mode. Then I reran the process using BOARD DL, which got me stuck in a crazy Mini OS screen that I couldn’t get out of. THEN I got my good cable and reran again using the BOARD DL – this got me stuck in the AAT Mini OS mode with a message that said “Touch Screen Test Mode,” “Don’t Touch the Screen,” “OK”. This was so confusing, but after searching the internet, I
      pressed the “OKAY” button, then held the power button down and selected normal boot +power. All the while leaving the USB cable plugged into the computer. Then I reran the process with the instructions above, using the UPGRADE DL as you suggested, and it worked. I cannot believe it. Thanks for the time you took to post. Long story short, I had to run the instructions twice…once using BOARD DL, then next using UGPRADE DL.

  15. Im a relative noob to Android, loved kitkat but cant stand Lollipop even with the v20h update, which has given me more issues than Ive ever had with my LG. Im in Australia, so Ive got the d855 but not sure if either the European or Hong Kong firmwares will work. Any help would be appreciated!

  16. Had to disable anti-virus to be able to download LG FlashTool and stock firmware. Otherwise a page not available message would show.

  17. I don’t know what I did but my Verizon LG G3 has stopped going to the firmware screen when I press and hold the volume up button when the phone is turned off. I had done it a few times over the past few days but lost my nerve with respect to downgrading my firmware but now when I try to do it the screen just stays black. The power button still works and holding all 3 buttons still brings me into that key assign screen for answering calls or turning off the alarm but when I just try and up volume button alone it doesn’t do anything anymore.

  18. When using the LG FlashTool I get hung at 10% and it fails. Error I get is ” [14:14:45] We can’t communicate with phone 00000064. There is not a percent on my lg g3 Weird but I am using a virtual window 7 pro 64 bit on my iMac. Could be an issue with virtual drivers. I’ll try another pc later

    • I can only find one other person via Google that has had this error and it didn’t have any conclusion to it. Please let me know if you think the virtual machine was the reason for this error

  19. At first I panicked a bit, but then got confused. Flash Tool went red and communicated “Download FAIL” (I chose Upgrade DL), phone screen went red saying similar, but as I removed the battery and put it back again everything was ok and at the moment I’m finishing personalization.
    Everything’s all right for now, thanks for the tutorial.

  20. when i tried to run the Lg FlashTool, it kept on prompting me to enter some sort of verification. It also said parallel key not found or something like that.

  21. Help!! Im stuck at step 12 and im in a bit of a hurry here (personal issue heh heh..) so i downloaded the USB driver from the LG website but under the d850 model, not sure if it matters, but i installed it and the LG mobile USB serial port thing NEVER showed up under COM and LPT ports options, so i chose it under a different model the VS985 metallic black version and the driver name was different but it STILL didnt show up ): Please help

    • Hrmm, have you tried rebooting your computer after you installed the drivers? I can’t imagine that it would matter, but it’s always worth a shot.

      Do you have the D850 or VS985 variant of the LG G3? Again, I can’t imagine that the USB drivers would be very different but it would be good to know.

      Which version of Windows are you on? Do you know if you have USB 2.0 or USB 3.0 ports? I’ve read that the LG G3 can have issues with USB 3.0. And some have reported issues with Windows 8.

      Also, are you using the exact USB cable that came with your LG G3? There have been reports that other USB cables cause issues when downgrading

  22. thx so much, the freedom apk plus my phone upgrading to 5.0 caused it to not login to google apps, thanks so much

  23. Try many times
    Always stop and showed: *Failed Previousload* when waiting the the Gray Box

    How should i do to solve this problem?
    Sorry for my bad english

    • We had another user having the same error, see if their steps help you. . .

      “In my attempt to flash it, between steps 36 & 37 the flash tool changed to red and displayed “Download Failed”, and at that point the G3 decided to only boot into “Mini OS” and display a testing screen. This was using the “Board DL” option.

      I had a small panic attack, and then tried again, but changed the flash tool to “Upgrade DL” this time.

      It worked just fine, and I’m now back to the original firmware.

      Thanks for the instructions.”

  24. Manual mode? 2 megalock.dll folders confusing. same with the flash tool can you be a bit more specific please. Thank you

  25. This is what is happening when I launch Setup_LGFlashTool_1.8.6.527
    First, it says LG USB/Parallel Lock Key is not detected.
    I click OK.
    Then it asks for a country, ID, and PW login.


  26. Awesome I finally Got my VS985 Downgraded from 12b to 10b after 2 days days of failed attempts. It kept faling when changing to download mode.. What I found is i bought a G3 off of Craigslist I thought it was the orginal cord but it wasnt so i used my cord from my GS4 and it worked I used usb port 2. Thank you for this Now I Have ROOT!!!!

  27. I’m stuck at the first Firmware Update screen. I am not using the original usb cable and also have it plugged into a usb 3 port. I can’t seem to get out of the screen, and am too scared to unplug the usb. I do not know how to get out of this situation, can someone please help?

    • Unless you have flashed something incomplete, then you might just be able to reboot it and get back into Android. Or maybe reboot into recovery mode and do a factory reset(if the former doesn’t work)

    • I’m sorry that you didn’t realize this was going to erase all of your data. Things like external SD card data should be left intact but everything else will be gone. I will add this bit of information to the tutorial

  28. well my LG G3 D850 as it shows in pic failed i have tried different cords 4 different usb slots and still get the following first i did it phone had blue screen but a number 2 and tool said fail and now after numerous trys with ports cord and upgrade and board i’m not even getting it to change to download mode

    • I’ve been looking into this error message and I might have found a couple of solutions.


      this person says “For all of those on windows 8/8.1 with the “can’t change to download mode” issue, do the following: Right Click on the “LGFlashTool.exe” -> Click on “Properties” -> Go to “Compatability” tab -> Check the box “Run this program in compatibility mode for:” then select “Windows 7” from the drop down menu. -> Click “OK”. Now try the process again.”

      I also found this


      This person says “RSo i got the same “can’t change to download mode” Here’s what I did to bypass that, don’t do anything after that error occurs. JUST unplug the USB from the phone and back in and it should reconnect and bypass it and continue the process within 2-5 minutes!”


      “Oh, don’t wait for the Flash tool to say PASS, cuz mine didnt and failed. Quickly remove the usb, and the battery once you see the FACTORY RESET 3 , not the #2, but the #3. and your phone should reboot just as fine.”

      Let me know if either of these tips help to resolve that error you are experiencing

      • Dear Android Explained.

        Have you found anything else about this error?
        In my case I did the process from step 1 to 36/37 where it only reached Factory Reset Status 2 and I got an error message and download fail, don’t remember at what percentage though.

        So I unplugged it and reset it and it just takes me to the blue screen again with ” Factory Reset Status 2″
        Then I tried to do the process from start again and I get stuck on “Can’t change to download mode”
        I have tried the cable that came with the phone and also an old usb2 cable. I have tried “Upgrade” and “Board”, I have tried compatability for windows 7 both to “upgrade” and “board”.
        I also do not get into the AAT screen.

        Please help 🙁

  29. Stupid AT&T. Woke up this morning with a Lollipop Update and No Root. About to down grade now. Any suggestions on keeping this from happening again?

  30. I haven’t had a windows machine in years. Is there any way to do this from mac OS X? Trying to flash devices from an emulator is hit and miss and I’d rather not brick my phone.

  31. I tried TOT method to flash my ROM to lollipop but still cant root my phone (LG G3). To downgrade, I would need stock ROM for LG G3 (32 GB) Singapore region (v20c). Any suggestions?

  32. I am getting a strange error when I click the yellow arrow. After a second it says in a pop up window “Failed PreviousLoad()”. I don’t know how to fix this. Can you help?

    • From the little bit of Google searching that I did, it seems like you have a bad download(aka it became corrupt while you were downloading it). Some have suggested downloading the firmware file again. Some have suggested trying a different browser. One user said they needed to download it on a different device altogether and then transfer before it would work properly. So all signs point to a corrupt/incomplete firmware download

      • As it turns out, I accidentally deleted the folder the .TOT file was in. I restored the folder and successfully downgraded my AT&T LG G3. Thanks anyway.

  33. Hi I did this and it worked fine, but I’ve got user data on it for some reason, apps that shouldn’t be on there, can anyone help.

      • No data in the apps, some apps cant be deleted as there actually in the phone like bloatware, so have to disable them, must of been 100 apps, french ones, i used the right firmware for my phone, i did it to my phone it worked fine, tried it on my sons it worked but with all these apps on it.

  34. hey i am having a problem every thing go’s good until the end my phone boots up and lg flash tool gets stuck at 94% and my phone says factory reset status 2 and then i take out the battery and reboot the phone and its stuck on 2 got any help?

  35. You are awesome!!! I just bought my phone already rooted and naively “updated” the software through a prompt and couldn’t get past TWRP. Thanks to this I have a working phone. I may even root it again, just happy to have a working phone now though. If I may suggest, between Steps 36-39 My phone did some strange things (went black a few times, vibrated) not mentioned in the steps and I was freaking out inside for a few seconds thinking I had bricked it. Perhaps a more generalized expectation and message of reassurance can be added here… “your phone may do some wierd things, be patient and wait for the blue screen”. 😉

  36. Folowed the guide to exact.
    The only thing is when i started the FlashTool – a dialog with 4 radio buttons opened, I did not know what to do – so i picked 3-th from Top to bottom.
    I am with LG G3 D855 (my version was v20h)

  37. my device is D855 16GB. but not sure whether taiwan or hongkong firmware..cani use either one of them? or can i use D855 european version?

  38. Hi! Is this tutorial will work for D855 v20h? Want to downgrade to KK,, Dont like Lollipop.. Thanks in advance!

  39. Thanks v much, it all worked just as you detailed here except my PC needed a restart to install the G3 USB drivers so testing what can be seen in device manager before entering flash mode on the phone might be a good idea.

  40. I am finding it impossible to activate the LG FLASH TOOL as it is asking for a I and Password. Please help as I’m losing my sanity over this. Thanks very much.

  41. I just upgrade to lollipop and the upgrade went fine Saturday. The only issue I had was fairly noticeable battery drain. Followed your instructions and the downgrade went perfect. Thanks a lot. This was a lifesaver!!!

  42. Thank you for this guide. Everything work perfectly. I had some issues with downloading the LG drivers but it turned out my USB cord was broken so once I swapped it out everything went as planned. I also used your tutorial to unlock my device and that worked perfect as well. THANK YOU again.

  43. Just fyi. I did the above for my Tmobile LG G3 purchased only 2 weeks ago. After using the correct firmware mentioned above “Download T-Mobile D851 LG G3 Stock Firmware” The sim card is no longer recognized at all. My phone service says the phone service is disabled. I can scan for networks and see them but not connect to them. I can manually set an APN to no avail. Whatever this tool does, it screws up your sim. Funny thing is if I use the authentic lg flash tool to flash back to lollipop (recovery) the sim card works immediately.

    • I wonder if this has something to do with the modem. Did you try finding a modem image to flash in a custom recovery or did you stay complete stock?

      I’m sorry there was an issue during this downgrade for you. I will look into this and see what I can find

      • I did not find a modem image. I actually am not sure what that is so I will research it now. I am trying to see now if I can flash back to kitkat with a kdz image instead of TOT to see if this fixes the issue. Thanks for the response. There was one other comment on here from someone who also said their sim card was not working. It however doesn’t have anything to do with removing the sim card before flashing, it seems to actually be something wrong with the stock firmware. Can you expand on the modem image?

        • Here is a link to some of the KitKat modems


          After you update to Lollipop, a modem image is flashed onto your device that only works on Lollipop. If you downgrade, it’s possible that the downgrade didn’t flash the KitKat modem.

          I’m not sure how this works with downgrading with LG Flash Tool on the T-Mobile G3. But I think it’s worth checking out that thread and seeing if you can flash those modems to get it working. Those are zip files and would require you flash them in a custom recovery though(if that’s something you don’t mind doing).

          If you want to stick with stock though, maybe it is a good idea to find a different source of the image. Maybe trying the kdz instead of the tot.

          Let me know how this goes so I can add a bit of information to the tutorial once a resolution has been found.

    • Yes, since we’re flashing official LG firmware images with this process, it will work on all carrier devices. You just have to make sure you download the firmware that is specific to your device(model/carrier)

      • hey buddy, just wanted to know that, After downgrading to android 4.4.1 from 5.0, can we again upgrade to 5.0 with auto update (upon degrading, can we get automatic update from LG or we have to upgrade to new upcoming version( 5.1 or 5.2 ) manually ?? ) .

        i am downgrading android because some of my softwares are not running on version 5.0, those software were running fine with 4.4.1.

        please drop me mail on vikas.naik19@gmail.com with answer please.

        thanks in advance.

  44. This comment is for anyone using T-MOBILE. I just had some trouble with this guide. I did everything in order and it all went smoothly. I was back to Kit Kat. But for some reason my sim card wasn’t working. I could not connect to t-mobiles network. Man was I pissed. I got back to Lollipop and COULD NOT STAND IT ANY LONGER. I tried this method again and after downgrading I was stuck with the same problem (Sim card not working). While my phone was still in the initial set up mode (sim card not working) I plugged my phone back into my computer. Almost instantly the sim card started working and I am now fully connected to T-mobiles 4g LTE network. NO PROBLEMS! BACK TO KIT KAT!!! If for some reason I have problems later on with the sim card, I’ll get back on here and let you guys know. Thank you for this guide. I think it might be wise to add a warning to T-Mobile users about this potential problem in the guide. Thank you again! Oh and screw ANDROID for releasing a TERRIBLE update. Who in their right mind would trade a Kit Kat bar for a boring old Lollipop?! Hehe. 🙂

    • I definitely will add that bit into the tutorial above. Thanks for the detailed feedback and I’m sorry that you had to go through those troubles with the tutorial

      So while you were in the Android setup phase, after downgrading, all you did was connect the phone to the PC with the micro USB cable and it fixed it? Were any programs like LG Flash Tool or LG PC Suite open?

      • I’m also on T-Mobile. After updating to Lollipop, my wifi was painfully slow, wifi calling didn’t work, battery discharge was terrible and HD voice didn’t (unfortunately, still doesn’t) work. After two calls to T-mobile and one call to LG, neither were able to help, other than LG recommending I ship them my device for two weeks so they could downgrade to 4.4.

        Dude, your guide is an absolute life-saver! Very easy to follow and I had no issues with the flash procedure.

        BUT….I did have the SIM card issue. I tried plugging in at different points during the initial setup to no avail. So, I decided to test another SIM card in my G3 and it still didn’t recognize. I’m not sure what changed, but after returning my SIM card to my device and rebooting, it began recognizing it again.

        Other than that little (major) scare and the HD voice indicator still not appearing, my wifi is much faster and wifi calling works!! I feel like I can finally use the device to its fullest potential!

        In short, THANK YOU! But T-mobile users beware, the SIM card issue may be a problem for you.

        • This SIM card issue sure does sound strange. I assume you also tried multiple reboots before you ended up swapping SIM cards?

          Either way, I’m very glad to hear that this downgrade worked for you and that it saved you the hassle of sending it back to LG. Thank you for the detailed feedback here as well

  45. Hi. I am from Bangladesh and I just upgrade to lollipop my LG G3 D855 32GB with “LGMobile support tool” and I have a issue that my phone does not support my sim card it says “Emergency calls only” . I think it’s a bug. then I downgrade it to Kitkat but the problem remains same and the most important thing is my device model number change to D855V. I check my IMEI it says D855 and all ok and it’s a international version. now it does not support my sim card. I don’t know what to do? Pls pls pls help me….

      • How can I find the correct firmware. Please help me. I install D85520B_00.kdz is it right or wrong. my phone’s IMEI is 354153063020258

        • I’m not sure 🙁 I only have experience with the ones listed here. If I find something though, I will definitely let you know. Also, if you end up finding something that works, please be sure to come back here and let us know what did the trick

  46. Hi thank you for the tutorial. Everything ran smoothly but when I try to boot my phone up at the very end, it does’t get past the LG starting screen with the flashing LED. Any suggestions?

      • I think thats where I went wrong. I downloaded Bell initially but this phone is originally from Rogers. The colour is blinking every green and blue. Is there anything I can do?

          • If your device is from Rogers, then you should definitely download the Rogers firmware. Booting your LG G3 up into Download Mode and doing this entire tutorial over(except with the Rogers firmware) should be all you need in order to get it working.


            This person seems to have the same blue/green LED blinking issue and it looks like they were able to solve it by using a different/correct firmware file that was linked to. Maybe you can follow what they did but, of course, using a firmware for your model

          • I did try to do it all over again with the Rogers firmware but unfortunately it led to the same result. Does this mean I bricked the phone? If so, soft or hard brick?

          • You have definitely ‘soft bricked’ the phone but it is able to be fixed. The only thing I can suggest is trying other firmware files. Maybe redownload the Rogers firmware, look for another rogers firmware from a different site.

            As long as you can get into Download Mode, the LG G3 isn’t ‘hard bricked’ and it is fixable. You just have to figure out what is causing the soft brick.

            If you end up figuring it out, please remember to come back here and let us know. If someone else ends up experiencing the same thing you did, your feedback about how you fixed it could help

  47. I greatly dislike the upgrade who thought of getting rid of the silent mode with pressing a simple button I hope they don’t have an umbrella nextbrainu day.

  48. I am having trouble with step 27, i have .TOT file but not sure where or how to click the .dll file on the flash tool.

  49. Hi everybody, I follow your instructions step by step and after the process has reached 80%, LG FlashTool program says “Download failed” and my phone does not want to turn on anymore.. Even the screen does not turn, no leds, nothing.. I tried to push Volume up button and power on/off button at the same time but nothing happens, the screen remains stucked and no backlight. Is there any mean or solution to fix this really annoying issue ? Some rude things to do with a executable file or .bat file ? Please if you have any idea, HELP ME !!!

    • Another reader had something similar happen to them and this is what they said. . .

      “I had a small panic attack, and then tried again, but changed the flash tool to “Upgrade DL” this time.”

      So you should be able to boot back up into the LG G3 Download Mode and try this process all over again. This time, change the Flash Tool option to ‘Upgrade DL’ and it should go through that time.

      If that fails, then it could be from the USB cable and you could try using another. Some have had issues with Windows 7 vs Windows 8. Some have even had luck by downloading the firmware file again(from a bad download). But changing the Flash Tool option to ‘Upgrade DL’ should fix the issue you are seeing

  50. Hey there, thanks for the help. I got stuck for a while because I forgot to unzip the BAT/TOT file. Ops… Apart from that, I would suggest not to forget the importance of pasting the MEGALOCK.dll file to the LGFlashTool’s file location. (copy and paste) into the lump file directory. Under the primary icon, right click it, go to properties and open file location. In there, drop the file. You’ll see that there’s already an identical named file, but it’s not the same code. Just drop it in there, confirm the overwrite and BAM!

  51. Hello.
    everthing went fine until I pluged back my LG G3 in order for the tool to start, but does not matter how long I wait it won’t start, help me please I dont like Android 5.0 :<<<

  52. Hi. I followed the instructions but at the end I got a fail message as per the attached image. My phone screen was dead at this point. I tried unplugging the USB and replacing the battery, but the phone won’t turn on or respond in any way. It won’t boot into download mode either using the volume/usb method. Any suggestions, or is my phone now bricked?

    • If you can’t get into download mode then it is probably bricked 🙁 This shouldn’t be possible though. Have you tried pulling the battery and then trying to boot it? What about keeping the LG G3 plugged in for 3-4 hours and then trying?

  53. Hello

    I need some help.i flashed a wrong kdz file on my lg g3 D855 after the flash my phone turned off and now its not booting up and also not going to download mode what should i do?

    Can anyone help me with it??
    My gmail is

  54. it worked by i got many more apps installing in my lg g3 and i ant uninstall them some of them are A1 Apps, 1881 Mobilsok, Amazon , amazon kindle,app store , app advisor and many more about 100 + how can i get rid of these apps please help

    • Hi Talha,

      These sounds like pre-installed applications and you might not be able to uninstall them without root access. The thing I would try is to go into the Settings, then find the Apps section. Swipe over to the All column and then locate the apps that you want to get rid of.

      Tap on one and then look to see if you have an uninstall or a disable option and then tap on it to get rid of it.

  55. Im talking about these apps there are many more otger than these. How can i uninstall then there is no option in apps to uninstall them

  56. After using the KDZ method, my LG G3 cannot connect to the network. I get the “service disabled”, “no Service” and sometimes it connects to the operator for some seconds. It is important to say that before the flash, the phone was working fine, and connected normally to the network.

    Troubleshoot already done:

    1 – Firstly, I flashed using the D85520B_00.Kdz file.

    2 – When I realized that the error, I thought this might be a version problem, so I downloaded D85510e_00.kdz version and re-flashed downgrading to 4.4.2. However problem remained.

    As a comment, I also noticed that it changed from version D855 to D855V.

    What should I do?

  57. Hi, My LG G3 D855 version 5.0 and it’s Patched. when I try to do step 24. Open LG FlashTool, then step 25. then on 26. Click the “…” Button at the Top Right’ its shows me wrong DLL. On step 27. I also tried to Locate the .DLL File from the Firmware Download Page, but I couldn’t find any DLL file, there is only one DLL file comes with flash tool, and also on the extracted stock firmware file there is only one single file as well. Could you please explain no 27. Locate the DLL File from the Firmware Download Page: is there any separate file on this page that I have to download. Please do reply Thank you so much.

  58. hi, i did everything that was described in your steps. but im getting “cant change to download mode” error in 14 secs time. please help!

  59. do you have stock firmware for lg g3 cat 6? lg-F460s…or can I use the korean f400s as well? thanks

  60. I don’t understand what I am doing wrong here.
    Step 28: after locating and adding the .dll file, I get an error message “wrong dll file”. The dll that I’m using is “LGD850_20140613_LGFLASHv160.dll’ which I’ve downloaded from the link that you’ve provided. Once that failed I tried getting the file elsewhere such as lgg3root.com. Which still results in the same error message. Any insight on this ?

  61. do you have stock firmware for lg g3 cat 6? lg-F460s…or can I use the korean f400s as well? thanks

  62. Hi, I followed the steps to downgrade to Factory reset, and after 89% of advance appear me the next picture and after that the lg Flash tool stop.
    I turned of, on the phone and problem still, same page appear.

  63. Worked a treat thanks! Can I confirm if I update software to Lollipop now with the phone rooted it will remain rooted but with the updated software?

    • That is not likely to happen but some users have reported that it does work that way. Others have reported that when you reboot after accepting the OTA, it will almost immediately reboot again and take you back to the non-updated firmware. Some others will get a pop-up message saying that the LG G3 detects root and will not apply an update.

      It all just depends on which carrier/mode you have, what you have done since you have rooted, etcetera 🙁

      If you try though, please come back and report your findings

  64. Thanks for this detailed tutorial. Can anyone confirm or deny that downgrading from Lollipop to KitKat using this method restores the KitKat modem?

  65. Worked great! Except my mobile data isn’t working. I can’t connect to LTE or 3G Networks, any solution to this problem?

    • Hrmm, are you 100% sure you downloaded the right firmware for your specific model?

      If so, then the first thing I would suggest is to dive into the APN settings and make sure it’s set to the APN if your mobile network. Even if it’s set right, it would be a good idea to delete the current selected one and add it back in, followed by a reboot. In case there was some corrupt data on the install or something

      If that doesn’t help then maybe a factory reset will. And if that doesn’t help then you might want to do another downgrade with a freshly downloaded firmware. In case the one you got before was corrupt upon downloading it

      Let me know if this does or does not help. Or what does work if you ended up figuring it out

  66. Thank you so much for this step by step I needed to revert from lollipop and this worked perfectly in usb3.0 and using different cable as well – I am Canadian on fido network and the rogers rom worked perfectly

  67. Can Someone Make A Video And Post It On YouTube Because Im Struggling With The Process ;/ . I Would Gladly Appreciate If You Do So 😀

  68. Can Someone Make A Video And Post It On YouTube Because Im Struggling With The Process ;/ . I Would Gladly Appreciate If You Do So 😀

  69. I tried this on my ls990 but when the grey screen pops up it gets stuck on the Checking CRC screen then it says it failed. Anyone know how to fix.

  70. I have some heat issues also with this lollipop update. Can I expect a solution for this issue also by downgrading?

    • Downgrading the LG G3 should resolve any issues that have happened since upgrading to Lollipop.

      However, since downgrading will reset all of your personal data anyways, have you tried doing a factory reset since upgrading to Lollipop to see if that fixes the heat issue?

  71. I just dont know what to download i am using an indian version of model D 855 32gb …behing the battery it shows madi in korea …am really confused…pls help

  72. In the Canadian section of the Stock Firmware link there is Bell, Rogers and Videotron. I’m using Koodo and can’t find Koodo/Telus firmware anywhere. Anyone able to help? Thanks

  73. When I start the Flash Tool (which I downloaded from the link provided above), It first asks me to pick a factory. Options are: Korea, China/Brasil, Other. Which one should I choose? Does it matter?

    In Step 27: Please add “Click Open”, Otherwise Step 28 appears to be meant for the Open dialog box.
    In Step 28: There are 2 Add buttons in the active Window. I think that you mean that I have to click the top one (referring to S/W).
    In Step 29: Please add “click open”

    My problem is slightly different than what I see here. I have just bought a new sealed phone on eBay, shipped from China (D850 AT&T). I am using it with another provider (Consumer Cellular), but even though I did not root the device (I downloaded some terminal software and it seems to verify that the device is not rooted), did not mess with it in any way, The AT&T upgrade says that they believe that the device is rooted.
    Before I get myself deeper into the mess, I would like to make a backup of the current ROM content, so that I can flash it back if needed. Does this tool help me with that?

  74. when i open up lg flashtool, then i have to login to something but i dont know what to type… what is it?

    it says csmg authentication

  75. I am trying to follow the steps, but when I try and go to download mode,i just get a message saying that download mode is disabled by kill switch. Anybody have any thoughts about this?

  76. i’m stuck on Factory Reset Status 2 ! What should I do? I re-flashed the firmware including another one from a different website European 16gb but it doesn’t work. i bought it from Argos UK

  77. Worked great on WIndows 10, USB 3.0… definitely need to use the UPGRADE DL mode otherwise you get stuck in the MiniOS test mode. Thanks for the article, you saved my butt. Check out my free service http://www.notifyprice.com if you want to save some money this holiday season!

  78. Hi Guys, i already did all the steps and it already PASS! but my phone is sitll stuck! it still looping back. can anyone help me with this problem guys? thanks

  79. Thanks for this!
    What would be the issue with downloading the stock firmware *before* putting the phone in Download Mode?
    The firmware download is taking hours, during which my phone is unusable. Is there an upside to this?

  80. i have an weired issue. the imei no. that phone shows is not same with that imei that i see behind the battery sticker. in the recovery mode my phone shows ls990 but in phone it shows d855. please suggest me if i install stock ls990 firmware in my phone will the imei change into original one?

  81. At this step it doesnt seem to be doing anything, please help…tx
    It is stuck at ‘Ready’

    36. Let LG FlashTool do its Thing

  82. I have the lg g3 vs985, am i able to downgrade from 6.0 marshmallow to 4.4.4 kitkat? I have tried with lg flashtool with no success, says failed. I have downgraded previous phone lg g3 from lollipop to kitkat, but new phone doesnt seem to work, any suggestions? Thanks

  83. I tried this and the SIM card isn’t working (Tmobile).
    I’m going to try plugging it in again aand I’ll edit this if it works. Or I’ll try the board dl to see if that makes a difference

  84. those who are facing no network,imei null ,touch issue after update,stuck on logo,partations appear on dextop,stuck on fastboot mode,no download mode of lg g2,lg g3 i will solve this issue through teamviewer just msg me on my whatsapp no +917744894155

  85. I have LG G3 Cat6 F460L. I am on Marshmallow 6.0 . but i want to downgrade because i am unable to root it. I was using your method but getting error. snapshot attached here. kindly help me. thnx

  86. So far I have done two phones, the first one was on 23 and the second on 35b. The first went through with no issues, the 35b phone I needed to use the LGUP8974.DLL file instead of the one that ends in LGFLASHv160.DLL. Using the original file I would get the version check failed error. Once I figured out that one 35b I needed to use the LGUP8974.DLL file it got past that error. BUT about 80-85% of the way done (on the phone screen it said STAGE 2) just after one of the reboots it FAILED. I noticed that the device had been re-detected and the com port changed off 41. All I did was change the port back to 41 and the LG Flashtool detected the device again and it started the flash over. This time after the reboot around 80-85% it re-detected the device but the port 41 “stuck” and it completed the flash (blue PASS on the tool and blue Status 3 on the phone).

  87. Hi I have LG G3 Verizon Carrier unlocked mobile. IF downgrade will it Carrier lock my mobile again?
    I am using it in india. SO, it it carrier locks my mobile back, mobile will be useless for me.

  88. Hey Doug, thank you for the amazing tutorial but I got an issue here! I got the Canadian LG G3 D852 with Virgin Mobile and I can’t find a stock firmware anywhere! The link you provide only has stock firmwares for BELL Mobile and Rogers Mobile. How can I root my phone now if I can’t downgrade it?

  89. weird thread here, seems my screens won’t attach? I downloaded and installed the LG Flash Tool as per the instructions. I did NOT open until it said to. I was presented with three options (korean, something else and then a 3rd something else) and “for test” was at bottom. Not knowing what to press, I just clicked ok… well, now LG flash tool is prompting me for a User ID and Password. I am not able to progress pat this. I have un-installed and re-installed but the tool is still prompting me for an ID and password. Any ideas?

  90. That’s great and all, but is there a downgrade firmware from Marshmallow 6.0 to Lollipop 5.0.2? I don’t care for KitKat. My model is d851 and is T-Mobile. Just want to revert but I only see tutorials on how to do it from different models such as d855.

  91. Can someone plz tell me how to downgrade lg g3 d851 from marshmallow back to lollipop? I’ve been looking everywhere for a tutorial yet only found for d855.

  92. thanks for this. It worked for me perfectly. At the very end, LGFlash did have an error message that said something like download failed. But on my phone, I had the blue screen, Factory Reset Status 3. So just took out the battery, put it back in, turned it on, and everything worked fine.

  93. Okay, I’ve now spent over ten hours working on this, and I’m no closer than I was at breakfast! I’m running Windows 7 and don’t really have an option of trying this out on another computer; I no longer have the “original, factory USB cord,” as my 7-year-old trashes USB cords like most people go through underwear (but I have tried 4 different cords in 3 ports). I have tried uninstalling and reinstalling everything, redownloading the stock firmware – even tried the same file from a different site (I have an AT&T LG G3 D850). I’ve tried relocating files to different folders, switching from “Upgrade DL” to “Board DL” and back again; no, my ports haven’t switched on me, they’re still on 41 in both the Flash Tool and in Device Manager. I’m exhausted, and beyond frustration.
    Does anyone have any tips? I’m sick of my phone being stuck in a boot loop – which is basically where it’s been since Marshmallow hit, unless it’s on a charger (and even then it’s iffy). THANKS!

    • Erin, were you able to downgrade or at least get out of the boot loop?, I having very similar situation, any idea or sugstion will be apreciated.

  94. Hi! I’m following these steps and now I’m stuck at number 27 “Locate the .DLL File from the Firmware Download Page”. I don’t know where is that and how to locate. Can you help me?
    #I’m from Brazil and I downloaded the european version (D855 16gb) is there a problem?

    THank you

  95. My screen just say “Ready” I pressed the yellow arrow, ungplugged/plugged in usb, but nothing happens after that. I changed it to Board dl to see if that would change anything, but I’m still getting the same result. Am I missing something?

  96. Hello.

    What do you know about these error?
    I have a Korean F400S. I downloaded the related files but i get these error. I am tring to downgrade from 6.0 to the ones you shared here.
    What should i do?

  97. I doubt you will see this given the age of the page but ill try anyway. I instead see LGEandroidnet USB Serial port, when i proceed I get a “model information check failed” message. Any tips?

  98. Sir pls help me ….i done this process as u say so..but it cut at 94% and show error……and my phone will show only lg logo …….and nothing else….i remove the bettary and then also stuck on the lg logo …..and nothing….also its does not get download mode…..only show lg logo ……pls sir help me to solve this problem…….how can i get my phone back in normal condition.????pls help me sir……

      • Yes sir i try to get factory reset or recovery mode …but nothing happen….only show lg logo…after some minute it will show me fastboot mode started or some code….it also do not get into download mode….sir help me to fix this problm…..

  99. I keep getting the message “Wrong DLL File” when attempting to select the Megalock.dll – any suggestions?

  100. I’m stuck on #26. when I try to go to the DLL file it says wrong dll file. I’ve tried to download all the ones I can find for the g3 online but they all are the same..what now??? HELLLPPPP

  101. i met a friendly guy on xda developers with the same phone as mine he says he was able to downgrade his lg g3 as985a21 to the verizon variant the vs985a10 which in terms let him then root his phone with that firmware now i tried everything all the steps and i get this message i get why i get it but how can i make it go through it was he bullshitting me or am i doing something wrong.

  102. I got Download Failed. The last line in the window said ” Model Information Check FAIL!” Could it be that the Filename LGD852AT is actually referring to the AT&T firmware? Not Rogers…or are they supposed to be compatible?

  103. As old as this is I’m still seeing people with this phone and having issues. These are the issues I ended up with and the solution. Hopefully it helps others
    If you get Model Fail – Go to this link for the DLL File. https://www.reddit.com/r/LGG3/comments/3ov9x6/need_help_lg_flashtool_model_information_check/?st=iy4qdd7w&sh=1d88f77e
    If that doesn’t work change action Mode to BOARD DL not upgrade.(on the screen which you choose the files.)
    If you end up at the Mini OS Touch test stuck – Hold the power button press Okay, unplug the Normal boot.
    If after your boot your Sim does not work – Remove the battery and reboot again and/or plug back into usb for a moment then unplug.

    Of course I’ll note this was on a Tmobile d851. Took about 2 hours with the issues but I’m back on Kitkat.

  104. omgomgomgomgomg this site was my last resort and still to no avail could i get my device back to stock. this program kept saying model information check fail. ive been at this for the past 6 hours… also followed every step to a T. and same thing on other sites. I FINALLY GOT IT TO WORK! only by downloding and using LGUP with the stock DLL and stock software for my D835 🙂 🙂 🙂 now to root and go to cloudy 2.5 😀

  105. This method worked! I had to download the other DLL, LGUP8974. But once I used that with the LG Flashtool it went pretty smoothly. I am using Windows 10 Pro and USB 2.0. Now on to root!

  106. Dear AE, thank you very much for this helpful post. I have been having my LG G3 for 3 years now (purchased it in 2015). Everything worked great until last week (28.06.2018) it required a software update. Now the android version is 5.0 and the software version is V21a (Czech Republic) and the battery drains much faster than before. I guess the solution is to downgrade the software again, what do you think? The thing is I don’t know what Android and software version I had before. How can I find out? Once I find out, I guess the correct procedure will be to follow your guide.

    Thank you very much for your help!


  107. Thank you for this document. Can anyone translate it to Linux for me? I have tried other Windows procedure by running them through Wine but I get hung up on specifying the port number in Linux. I did have my LG G3 rooted while it was on Kit Kat but Google forced an update on the phone wiping out root.

  108. I downloaded the LG FlashTool zip file… But there isnt anything in the folder. (its completely empty). Is there any way to get these two files (the exe installer for LF FlashTool and that MegaLock.dll file) in any other way? Thanks!


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