Database Info

Returning To Stock Nexus One

FIRST AND FOREMOST: DISCLAIMER,
I am not responsible for any steps your take in modifying or following the steps described below. This is simply a guide to assist you with restoring your phone. If your break, drop, ruin, brick, wipe, slap, chop, honk, ding, open, slave or unock your phone and it does not respond how you expected sorry your phone, your responsibility.
What is described below worked for me.
Ok, after searching for hours or nearly days for a way to unroot and get back tot he stock rom that allows for Over the Air Updates (OTA's) I finally figured it out after piecing together tons of threads on related subjects.
Anyway here it is...
On my nexus one I was using a CyanogenMod Rom and wanted to revert back to stock because of a few glitches I didn't like. I was presented with tons of problems when trying to do so. This is what I did.
For dummies version:
GET THE NECESSARIES
(1) Downloaded the stock ROM FRG83 from Modaco HERE
(2) Unzipped this to a folder I created on my PC (I named it Platform-Tools)
(3) Downloaded and Installed the Android SDK. This comes with ADB and driver for your phone which is a must need. HERE
(4) Copied all files from the android/android-sdk/platform-tools folder to the folder I created earlier in step 2.
(5) Downloaded fastboot command (Available in attachment below)
(6) Downloaded flash_image.zip (Available in attachment below) (Optional - flash_image.zip only needed if using ADB method and is not described below or recommended)
UNLOCK BOOT LOADER
(1) Unlock Boot Loader (Yeah you have to do it). If not done you will get an error saying unable to verify signature when trying to load the img files.
-Boot in to boot loader by Powering on your phone while holding down the trackball
-Connect phone to your pc using a usb data cable
-on the boot screen it should say something like "fastboot usb" after doing so
-Type fastboot oem unlock
-Read the warning and accept it
(2) Boot in to boot loader by Powering on your phone while holding down the trackball
(3) Should say unlocked at the top
PHONE UNLOCKED AND READY TO FLASH YOUR PHONE TO STOCK
(1) If not done already Boot in to boot loader by Powering on your phone while holding down the trackball
(2) Connect phone to your PC with a USB Data Cable
(3) From your PC command prompt change directory to where you save your img files and the fastboot command stuff
(4) Type The Following In Sequence from your PC Command prompt:
fastboot flash boot (YOUR DIRECTORY)\boot.img
fastboot flash recovery (YOUR DIRECTORY)\recovery.img
(5) Boot in to recovery
-Select bootloader from the menu
-Select recovery from the next menu
(Wait, a triange with an exclamation mark appears)
-Press the power button along with the up volume button
(Boots to the android recovery menu)
-Wipe everything
(6) Reboot in to the boot loader and Type The Following from your PC command prompt In Sequence
fastboot flash radio (YOUR DIRECTORY)\radio.img
fastboot flash system (YOUR DIRECTORY)\system.img
When done reboot and enjoy your fully restored un-rooted back to stock nexus one and enjoy all your OTA Updates as they are released.
If there is something I missed or needs correction let me know and I will make necessary revisions.

pardon my ignorance but i was under the understanding that the Nexus One already ran Stock android

ThunderStick said:
FIRST AND FOREMOST:
Anyway here it is...
On my nexus one I was using a CyanogenMod Rom and wanted to revert back to stock because of a few glitches I didn't like. I was presented with tons of problems when trying to do so. This is what I did.
johnston9234 said:
pardon my ignorance but i was under the understanding that the Nexus One already ran Stock android
Click to expand...
Click to collapse
At the start he mentioned he was running cyanogenmod (quoted)...it's also mentioned in his signature.
Click to expand...
Click to collapse

Anybody that needs to download and flash an Original ROM obviously didn't follow the first rule of flashing. NANDROID BACKUP YOUR STOCK ROM FIRST!!!
To return to stock for OTA updates all you need to do is restore your Nandroid backup and reboot once. That's all.

[Guide] Returning to Stock and/or Unbricking your device Updated for Android 4.3!!!

First of all, I am in no way responsible for anything you do to your tablet period.
I have seen a couple of people asking how to return the Nexus 7 to stock after it has been unlocked, rooted and so on, so I figured I would write a quick guide as its super easy to do. Also, please make sure you make a backup of anything you don't want to lose. This is important.
Before you begin, please make sure you have ADB and Fastboot drivers installed and working.
1) Download the factory image for the Nexus 7 at https://dl.google.com/dl/android/aosp/nakasi-jwr66v-factory-d341d356.tgz
2) Extract the factory image into the same directory as your ADB and Fastboot executibles (e.g. "\android-sdk\platform-tools")
3) Plug in your device. If you are booted into Android, open a command prompt to your ADB and Fastboot directory, then type
Code:
adb reboot bootloader
If your device is powered off, press and hold both volume keys and the power button simultaneously. After holding all three buttons for a couple of seconds, your bootloader should launch. This should reboot you into the bootloader.
4) Type
Code:
fastboot flash bootloader bootloader-grouper-4.23.img
5) Next type
Code:
fastboot reboot-bootloader
6) Now type
Code:
fastboot -w update image-nakasi-jwr66v.zip
7) Optional: If you would like to relock your bootloader for warranty or security purpouses, make sure you are in your bootloader screen again and type
Code:
fastboot oem lock
8) If your tablet hasn't already rebooted automatically, type
Code:
fastboot reboot
That should do it. You should now be on stock Android 4.3 and ready to send in your tablet for warranty purposes if you so desire.
Additionally, here is an instructional video courtesy of XDA user SladeNoctis.
Also, thank you to XDA user Shano56 for the formatting help on this post.

chris.wueste said:
First of all, I am in no way responsible for anything you do to your tablet period.
I have seen a couple of people asking how to return the Nexus 7 to stock after it has been unlocked, rooted and so on, so I figured I would write a quick guide as its super easy to do. Also, please make sure you make a backup of anything you don't want to lose. This is important.
1) Make sure you have your ADB and Fastboot drivers installed and working.
2) Download the factory image for the Nexus 7 here
3) Unzip the factory image into the same directory as your Adb and Fastboot drivers.
4) Plug in your device. With the device on the home screen, type "ADB reboot bootloader" or if your device is off, press and hold both volume keys and press the power button. After holding all three buttons for a couple of seconds, your bootloader should launch.
5) This should reboot you into the bootloader. Now type "fastboot flash bootloader bootloader-grouper-3.34.img"
6) Next type "fastboot reboot-bootloader"
7) Now type "fastboot -w update image-nakasi-jrn84d.zip"
8) Optional: If you would like to relock your bootloader for warranty purposes, make sure you are in your bootloader screen again and type "fastboot oem lock"
9) I don't remember if the tablet automatically reboots at this point but if it doesn't just type "fastboot reboot"
That should do it. You should now be on stock Android 4.1 and ready to send in your tablet for warranty purposes.
Additionally, here is an instructional video courtesy of XDA user SladeNoctis.
Click to expand...
Click to collapse
You should change the title to [Guide] How to return to Stock / Unbrick your Nexus 7
Helps out those getting bootloops or softbricks from geting root access in certain ways or messing with the build.prop

SladeNoctis said:
You should change the title to [Guide] How to return to Stock / Unbrick your Nexus 7
Helps out those getting bootloops or softbricks from geting root access in certain ways or messing with the build.prop
Click to expand...
Click to collapse
Not a bad idea. Done and done. Also, I have proofread it several times over to ensure it is correct but would you mind making sure that all of the commands were typed correctly. My eyes are going crosseyed over here.

Nice guide man, I changed the format a little to make it easier to read. Use it if you want, won't be offended if you don't.
First of all, I am in no way responsible for anything you do to your tablet period.
I have seen a couple of people asking how to return the Nexus 7 to stock after it has been unlocked, rooted and so on, so I figured I would write a quick guide as its super easy to do. Also, please make sure you make a backup of anything you don't want to lose. This is important.
Before you begin, please make sure you have ADB and Fastboot drivers installed and working.
1) Download the factory image for the Nexus 7 here
2) Extract the factory image into the same directory as your ADB and Fastboot executibles (e.g. "\android-sdk\platform-tools")
3) Plug in your device. If you are booted into Android, open a command prompt to your ADB and Fastboot directory, then type
Code:
adb reboot bootloader
If your device is powered off, press and hold both volume keys and the power button simultaneously. After holding all three buttons for a couple of seconds, your bootloader should launch. This should reboot you into the bootloader.
4) Type
Code:
fastboot flash bootloader bootloader-grouper-3.34.img
5) Next type
Code:
fastboot reboot-bootloader
6) Now type
Code:
fastboot -w update image-nakasi-jrn84d.zip
7) Optional: If you would like to relock your bootloader for warranty or security purpouses, make sure you are in your bootloader screen again and type
Code:
fastboot oem lock
8) If your tablet hasn't already rebooted automatically, type
Code:
fastboot reboot
That should do it. You should now be on stock Android 4.1 and ready to send in your tablet for warranty purposes if you so desire.
Additionally, here is an instructional video courtesy of XDA user SladeNoctis.
If you want to use it and are too lazy to quote my post - http://pastie.org/pastes/4279753/text
The commands look good to me however I've never used "fastboot -w update" so can't say for that

Shano56 said:
Nice guide man, I changed the format a little to make it easier to read. Use it if you want, won't be offended if you don't.
First of all, I am in no way responsible for anything you do to your tablet period.
I have seen a couple of people asking how to return the Nexus 7 to stock after it has been unlocked, rooted and so on, so I figured I would write a quick guide as its super easy to do. Also, please make sure you make a backup of anything you don't want to lose. This is important.
Before you begin, please make sure you have ADB and Fastboot drivers installed and working.
1) Download the factory image for the Nexus 7 here
2) Extract the factory image into the same directory as your ADB and Fastboot executibles (e.g. "\android-sdk\platform-tools")
3) Plug in your device. If you are booted into Android, open a command prompt to your ADB and Fastboot directory, then type
Code:
adb reboot bootloader
If your device is powered off, press and hold both volume keys and the power button simultaneously. After holding all three buttons for a couple of seconds, your bootloader should launch. This should reboot you into the bootloader.
4) Type
Code:
fastboot flash bootloader bootloader-grouper-3.34.img
5) Next type
Code:
fastboot reboot-bootloader
6) Now type
Code:
fastboot -w update image-nakasi-jrn84d.zip
7) Optional: If you would like to relock your bootloader for warranty or security purpouses, make sure you are in your bootloader screen again and type
Code:
fastboot oem lock
8) If your tablet hasn't already rebooted automatically, type
Code:
fastboot reboot
That should do it. You should now be on stock Android 4.1 and ready to send in your tablet for warranty purposes if you so desire.
Additionally, here is an instructional video courtesy of XDA user SladeNoctis.
If you want to use it and are too lazy to quote my post - http://pastie.org/pastes/4279753/text
The commands look good to me however I've never used "fastboot -w update" so can't say for that
Click to expand...
Click to collapse
I updated the OP with your edits in it. Thanks for the help. I quoted you at the bottom

omg thank you so much. u saved my device

jarjar124 said:
omg thank you so much. u saved my device
Click to expand...
Click to collapse
Very welcome

Assuming you have a nandroid, can you boot into the bootloader, and simply ADB reboot recovery? Or does that bug prevent you from even doing that?

chrisjm00 said:
Assuming you have a nandroid, can you boot into the bootloader, and simply ADB reboot recovery? Or does that bug prevent you from even doing that?
Click to expand...
Click to collapse
In some cases due to the CWM not being official it cause bootloops by going to recovery in the bootloader.

SladeNoctis said:
In some cases due to the CWM not being official it cause bootloops by going to recovery in the bootloader.
Click to expand...
Click to collapse
There's a CWM official out?
Sent from my Nexus 7 using Tapatalk 2

chrisjm00 said:
Assuming you have a nandroid, can you boot into the bootloader, and simply ADB reboot recovery? Or does that bug prevent you from even doing that?
Click to expand...
Click to collapse
Assuming you have already flashed CWM, then the command would actually be fastboot reboot recovery. Not sure what but you speak of.

Shano56 said:
There's a CWM official out?
Sent from my Nexus 7 using Tapatalk 2
Click to expand...
Click to collapse
Yes. There sure is. If you have Rom Manager installed it can be flashed directly from there.

I dont think you can really hard brick this device anyways

I'm sitting here at the command prompt with it on "erasing userdata"
It's been a couple minutes and I'm freakin' out! How long is it supposed to take? Everything flashed correctly, if I start the device now will there be an issue?
EDIT: Nevermind, just rebooted from the bootloader in the tablet and it booted fine. I'll get the OTA to 4.1.1 and that should probably fix any outstanding little issues.

hard brick?
I am stuck at the Google logo with a padlock and I'm pretty sure I have a hard bricked tablet. fastboot doesn't see the tablet or my computer for that mater through dmesg.
I've rebooted it countless times with vol + and vol - pushed and any combo thereof. It will only turn off completely when the battery dies because holding down the power key for 10 secs just reboots it back to the Google logo in about 5 seconds. I guess at this point I'm just waiting for Google to give me a RMA for a refund and I'll move on unless someone has any other ideas?

chris.wueste said:
If your device is powered off, press and hold both volume keys and the power button simultaneously. After holding all three buttons for a couple of seconds, your bootloader should launch. This should reboot you into the bootloader.
Click to expand...
Click to collapse
Pressing and holding the Volume down + Power buttons works just fine to launch the bootloader (at least for me).
No need to press (and force) the entire volume rocker button at all.

nugalonious said:
I am stuck at the Google logo with a padlock and I'm pretty sure I have a hard bricked tablet. fastboot doesn't see the tablet or my computer for that mater through dmesg.
I've rebooted it countless times with vol + and vol - pushed and any combo thereof. It will only turn off completely when the battery dies because holding down the power key for 10 secs just reboots it back to the Google logo in about 5 seconds. I guess at this point I'm just waiting for Google to give me a RMA for a refund and I'll move on unless someone has any other ideas?
Click to expand...
Click to collapse
Try and press and hold just the power button for 30 seconds or so to re-boot the tablet and you should be fine and it should boot up just fine. From fastboot you cannot go into cwm recovery because of a bug.

I'm trying to return to stock but get this message in the window from the ADB command after flashing the stock ROM:
​FAILED (remote: (FileWriteFailed))
Anyone seen that before or have any ideas to fix?
I tried wiping cache/factory reset from CMW but no joy.

Thanks. Worked for me. I did get worried when i got (data transfer failure (too many links)) error when trying to flash the bootloader.
Turns out it was the USB port. I switched the ports and all was well.
But I followed the commands in side the flash-all.sh file
fastboot erase boot
fastboot erase cache
fastboot erase recovery
fastboot erase system
fastboot erase userdata
fastboot flash bootloader bootloader-grouper-3.34.img
fastboot reboot-bootloader
fastboot -w update image-nakasi-jrn84d.zip
---------- Post added at 02:16 PM ---------- Previous post was at 02:13 PM ----------
yeahthatsme said:
I'm trying to return to stock but get this message in the window from the ADB command after flashing the stock ROM:
​FAILED (remote: (FileWriteFailed))
Anyone seen that before or have any ideas to fix?
I tried wiping cache/factory reset from CMW but no joy.
Click to expand...
Click to collapse
Try the commands i posted above and see what happens

Nuts. I tried it on many USB ports and did your commands one by one. Ended up in the same spot. It happens when writing 'userdata'...

Motorola XT910 Bricked

good afternoon forum Mods if I'm posting in the wrong section I'm sorry and move where it should be post it at I couldn't find a way to open a new thread under Motorola all I was able to see was threads already posted
any way I'm in desperately need of help I have this Motorola XT910 which one was working just fine the only problem that it had was the wifi and bluetooth wouldn't turn on it's a LATAM device and it had 4.1.2 I don't know who updated to this version or how that's all I could see under about phone it has bootloader locked I couldn't tell you if it was root don't really remember I only had it for a couple hrs and decided to flash a different rom to see if the wifi and bluetooh option would be available
this is what I done to the phone so far i'm gonna start from when it was working
I install BMM and I follow all the instructions just like in this post http://forum.xda-developers.com/showthread.php?t=2260951 but phone never booted normally it just got stock on this screen with a gear looking wheel turning I did a back up of my system but could never go to it all i remember being able to go to was this screen on BMM where you can chose what system you want to boot but all I see was artmod rom and all the other system windows were empty so i was just stuck between this screen the gear wheel trying to boot the system and the screen where i could chose the system i wanted to boot into
no help there so battery was low so i removed it charged it with a universal charger over night boot into AP Fastboot and trying flashing the 3 folowing roms with RSD Lite 6.1.4 but every rom gives me the same error message CDT.BIN failed phone return fail
these are the roms i'm trying to flash
Branding: Retail Brazil
Version:9.8.2O-124_SPUL-17 Service
Android Version:4.1.2
with RSD Lite 6.1.4
Branding: Oi Brazil
Version:9.8.2O-124_SPUL-17 Service
Android Version:4.1.2
with RSD Lite 6.1.4
and one from UK with version 4.1.2 as well and no go also i have tried this flash tool HSD-pilots UNBRICK but always gives me error message when trying to flash the booteujb.img file i tried doing directely and as follow
1) download These fastboot files.rar (clink on text)
2)download retailEU. jellybean OTA
3)Download HSD-pilots UNBRICK.rar
4)UNRAR HSD-pilots UNBRICK.rar from step (3) to any new folder (lets name it UNBRICK)
5) UNRAR Fastboot files:
cdrom_signed
cdt.bin_signed
devtree_signed
ebr_signed
mbr_signed
recovery_signed
radio.img
system_signed
from step (1) to Folder from step (4) we named UNBRICK ONLY extract files i said
6)Connect your device to pc
7)open UNBRICK folder Hold shift and right click on white space -> then press OPEN COMMAND WINDOW HERE
8)flash files from step (5) by writing in the command window you opened:
mfastboot flash cdrom cdrom_signed
mfastboot flash cdt.bin cdt.bin_signed
mfastboot flash devtree devtree_signed
mfastboot flash ebr ebr_signed
mfastboot flash mbr mbr_signed
mfastboot flash recovery recovery_signed
mfastboot flash radio radio.img
9)with the phone still connected to PC open UNBRICK folder and tun Unbrick.bat.
10) after unbrick.rar flashed press power button once, and immediately hold volume up + volume down and press power again
11) go down to recovery and press volume up
12) when you just follow instructions in bat file. see android picture press volume down and volume up at the same time and wait for radio to install
13) after installation of radio wipe data and catch -> navigate to factory reset and do it
14) Then go to install update from external memory and install retailEU. jellybean OTA that you downloaded (you have to put it to your external SD card)
15) If all is fine it will update, just reboot and its unbricked
no luck what else can you suggest please any help would be really appreciated

sorry buddy but i didn't read all of your post. cuz i know it. if you can't flash your phone using fastboot recovery bootloader mode and ect... you need to flash using J-TAG or BOX , normal users doesn't have these tools, mobile fixers have these... that is the very last way of flashing...
if i helped you press THANKS button

m3ni said:
sorry buddy but i didn't read all of your post. cuz i know it. if you can't flash your phone using fastboot recovery bootloader mode and ect... you need to flash using J-TAG or BOX , normal users doesn't have these tools, mobile fixers have these... that is the very last way of flashing...
if i helped you press THANKS button
Click to expand...
Click to collapse
I know what J-TAG is but when you say box what box are you talking about?
also what is this error I keep getting in RSD Lite CDT.BIN phone returned fail I couldn't find any useful information on the web or here

re
prz0007 said:
I know what J-TAG is but when you say box what box are you talking about?
also what is this error I keep getting in RSD Lite CDT.BIN phone returned fail I couldn't find any useful information on the web or here
Click to expand...
Click to collapse
because no one faced that problem, even me, but i see lots of pepple failing to flash theyr phones and using j-tag, ok i don't know what is the name of box there, but here they call it box, it will cpnnect to COM1 port and a tiny box is in middle and it will connect to phone! it has its own flash tools and... the box is 20-30$ i never buy one of them, i just pey them for flashing (for some phones that i can't flash)
we can't do this, so maybe you can? i suggest you to call your mobiles caustomare care service, and tell the problom to them, they know what to dp
and i read some where that motorolla uses mtk chipsets
so try a search of " how to flash mtk phones "
it use sp flash tool, sorry
and other thing, i'm so sleepy i cant type any more, if i helped press thanks...

Phone boots into fastboot, system files corrupted

Hi! My old phone is booting into fastboot mode, when I try to boot normally I get a black screen, the "Power off" button appears when I hold the power button. The bootloader is not unlocked and the phone was never rooted. Wiping the user partition does not help. It is visible in fastboot mode and I can enter stock recovery, though trying to adb sideload a stock rom returns an error (footer is wrong; signature verification failed). Trying to fastboot boot twrp or recovery.img doesn't work either. I've ran out of ideas, what should I do to get this phone to work?

Try flashing the stock ROM with fastboot. I'm pretty sure ADB doesn't let you flash onto your phone because using your phone with ADB means that it's still powered on - which can cause some issues. You can also try and unlock your bootloader through fastboot, and then flash a recovery and custom ROM.

Both failed. I attached the errors I recieved.

crepper4454 said:
Both failed. I attached the errors I recieved.
Click to expand...
Click to collapse
Try "fastboot bootloader unlock", maybe. Also: Is there a flashall.bat in the stock ROM folder? If there is: Connect your device while in fastboot, and double-click it.

crepper4454 said:
Both failed. I attached the errors I recieved.
Click to expand...
Click to collapse
Try this maybe. I know you can't wipe through the stock ROM, so, try the command: "fastboot -w". That'll wipe everything off the device.
[INDEX][Osprey][Merlin] Moto G Factory Firmware Images
Disclaimer: I am not responsible for anything that happens as a result of flashing these files. Your destiny is your own. Moto G (3rd Gen) Factory Firmware Images - Provided by Firmware TEAM - Please report broken links. New Mirrors welcome...
forum.xda-developers.com

I can wipe through stock recovery. I did fastboot -w and it cleared the cache and userdata partitions, they were already clean afaik. Typing fastboot bootloader unlock returns unknown command. There are no .bat files in my firmware. I can try downloading one from the site you linked, but I don't know what to do with it if fastboot flash does not work.

crepper4454 said:
I can wipe through stock recovery. I did fastboot -w and it cleared the cache and userdata partitions, they were already clean afaik. Typing fastboot bootloader unlock returns unknown command. There are no .bat files in my firmware. I can try downloading one from the site you linked, but I don't know what to do with it if fastboot flash does not work.
Click to expand...
Click to collapse
Try this: https://forum.xda-developers.com/t/guide-osprey-fastboot-flashing-factory-firmware-images.3187750/

It says there that the "preflash validation failed" error occurs when the firmware being flashed is older than the one already installed. I will try downloading a newer version and flashing it. Will update here.

Update: I have dowloaded a newer rom and tried to flash it. This time got different errors (picture attached, this went for every sparsechunk). I think I know the reason but I do not know how to solve it. This might not be the exact stock rom of this phone so I cannot flash it with a locked bootloader. Could someone help me finding the correct rom or suggest a different solution?

Yooooo. I have the Moto e5 Cruise and so does my wife. We bought them in 2018 from Cricket and last night hers went to emmc failure, also known scientifically as 'no worky' mode.
The phone would only load in fastboot and had tried to use my Moto RSD tool to reflash but the phone would not detect in anything but fastboot mode.. Here's where it gets interesting....
There is a piece of software called the Lenovo (which now owns Moto) Rescue and Smart Assistant that can reflash your phone back to factory, no matter your sub-variant (cricket, metro, etc). Without having a fresh backup on hand, you're going to be beholden to the last cloud sync or manual backup you have because all data will be wiped in the below process.
BTW: Just run the assistant as it seems to be the easiest 'back-to-stock/working' tool I can find. Going to fastboot alone yielded weird errors since i didn't have the unlock code for the 'fastboot oem unlock [code goes here]' command.
**RESTORATION PROCESS**
This will apply to multiple Lenovo/Moto Mobility devices. Unknown at this time how many have been impacted by this seemingly pre-planned failure on Lenovo's part.
If your phone is stuck in fastboot mode where MTK download mode does not load, nor does adb, follow these simple steps:
(NOTE: BACKUP YOUR FILES IF POSSIBLE)
1. Click the link above to be directed to the Lenovo software download page and run the installer on your PC (Sorry Mac users :'().
2. The software, once installed, will require you to sign up for OR link a google, fb, g+, etc account to it for purposes of creating a Lenovo ID. Once signed in, click on 'Rescue Now'.
3. With your phone in fastboot mode, allow the software to download the firmware for your phone.
4. Once the firmware has finished downloading and validating, click on 'Rescue Now' once again. Your phone will begin the reflashing process.

That... actually worked. The program found the required ROM and flashing went without problems. Thank you very much @kmt5150 .

crepper4454 said:
That... actually worked. The program found the required ROM and flashing went without problems. Thank you very much @kmt5150 .
Click to expand...
Click to collapse
No problemo! Glad it worked!

Unlock TCL 20y (6156D) phone. Possible?

Hello,
I have a TCL 20y (model 6156D) phone and i'm trying to gain root access in any way.
I've tried to enable oem unlocking and go to fatboot mode, but the command
fastboot oem unlock returns "FAILED (remote: 'Command not supported in default implementation')".
On producer website i can't find this model and in the "repair software" this model (6156D) is missing.
I don't have any recovery file (stock or trwp), and i don't know how to dump original recovery to file (for install magisk, but anyway i think i can't flash modified versions without unlock bootloader).
Is there anything i can try?
---
Edit: I finally found the original flash tool at the following url:
Modello
www.tcl.com
https://www.tcl.com/content/dam/tcl-html/TCTService/support/tcl-20-r-5g/Mobile_Upgrade_S_Gotu2_v1.1.5_Setup.exe
It seems to support model 6156 and, with connected phone, it has downloaded a lot of files and created a folder "6156D-2ALCWE12\ANAJEAJ0" (model\version) with a lot of files with MBN extension and a zip with system.img inside.
Maybe these files may be useful to root the phone. Anybody knows how to open MBN files?
--
Edit: I've notice a strange thing. When I boot to recovery, i see two interesting options:
- Enter fastboot: this stats "fastbootd", a graphical menu with a few reboot options. In this phase the computer recognizes the phone with fastboot driver and list it with "fastboot devices" command.
- Reboot to bootloader: this clear the screen, writes "FASTBOOT>" in the low position of the screen. In this phase the computer recognizes the phone with adb driver and don't list it in fastboot devices nor adb devices.
I've also tried to flash magisk apk (renamed as zip) with adb sideload, but as expected i got Error 21.
Is there a way to sign any root manager or su binary and install it using this method?
What am i doing wrong?

Hi!
I've managed to unlock the bootloader on a TCL 20Y by following this guide: https://romprovider.com/tcl-20y-unlock-bootloader/.
I used the mtk_gui utility, which is really straightforward. The only tricky thing was going into brom/preloader mode - sometimes it works, other times it doesn't.. The trick is to hold both volume buttons while plugging in the USB cable to the computer.
Then, I've also managed to root the device with Magisk by patching both the boot_a.img and boot_b.img images and flashing them using fastboot by following the official guide: https://topjohnwu.github.io/Magisk/install.html.
Haven't yet played with the orange state disabler as I've read that it can result in a brick.
BR

Hey there!
With bevvare's help I was also able to root my TCL 20Y without much issue, though I encountered a few minor differences and details so we agreed it would be good if I wrote them down here.
Regarding the first guide used to unlock the bootloader:
The mtk_gui utility packed in the, as of today, latest release of mtkclient (1.52) refused to launch. That wasn't too bad seeing as the guide provides the necessary commands, but it's something to keep in mind.
In addition, I found that the phone would stop accepting commands after the first one was issued or after the log got too long*. This might have only been an issue on my end, but just in case, this is how i ran each command:
-Turn the phone off
-Hold the power button along with both vol+ and vol- (you may plug in the phone at this stage)​-While in the Recovery Mode screen, issue the command on your terminal​-Select the option to restart the device in the recovery screen, then hold both vol+ and vol- until the terminal starts printing output (the phone's screen will stay off while this happens)​-After the command has executed, unplug the phone (probably optional) and hold all three buttons again to restart and boot into recovery​Repeat as needed​​
* Remember how I mentioned the command seemed to fail if the log got too long? Well, this is what happened to me with the very first command on the guide (the one that erases three partitions at once). Just to be sure, I erased them separately using the same command.​​PS: booting into recovery first may not even be needed, I just found it easier that way.​
The guide provides two unlock commands, the first one being python mtk xflash seccfg unlock, this ran without issue and triggered the orange state warning on boot. The second command (fastboot flashing unlock) refused to work, but the bootloader was nonetheless unlocked.
Also, the guide provides the relock command right after the unlock one as if it were the next step to take. This might be obvious, but don't relock your bootloader until after you're done flashing the new boot image (even then there's no real reason to relock it).
Regarding Magisk's guide on patching boot.img:
Magisk failed to patch boot_b.img. This turned out to not be a problem because my device was using the boot_a partition as the active one (I used this guide to check https://krispitech.com/check-partition-slot-a-b/ )
In order to get the necessary files, namely boot_a.img and vbmeta_a.img, I used this guide to dump all the partitions within the phone into my PC: https://forum.xda-developers.com/t/...sing-mtk-client-oppo-reno6-5g-mt6877.4406069/
You may also decide to dump only the two partitions you need, in which case you could issue the following command instead: python mtk rl boot_a,vbmeta_a boot_a.img,vbmeta_a.img (this assumes your phone is also using partition A, adjust as needed).
If you used the above guide to dump all the partitions, the files you need will have the .bin extension, just rename them so they are .img files instead.
I recommend flashing vbmeta_a.img (it's optional and doesn't need to be patched in the Magisk app like boot_a.img). Otherwise your device will print a spooky warning at boot about being corrupt and demand you press the power button, which is annoying.