Database Users

Un-debrickable state ?

Hello guys,
I'm fairly certain I'm stuck in an un-debrickable state but I'll ask just in case. My phone is F800K.
I was toying around with LGUP in order to downgrade and root my phone. So far, so good.
I then tried to update to the latest android 9 again, but keep the root active. That's where things started to go south, so I decided to go back.
I followed a couple of "back to stock" guides but now I'm screwed.
- The phone does not boot.
- Download mode is broken, the phone doesn't connect to my computer while in download mode, so it's unusable.
- TWRP is gone. When I try to boot to recovery after yes both times I get nothing. Not the stock recovery and not TWRP, it just tries to boot as usual.
- Can't seem to go back into fastboot either. I tried VOLDOWN + plug-in the phone about 200 times now, to no avail.
Is there another way that I'm missing ?
Thanks.

growiel said:
Hello guys,
I'm fairly certain I'm stuck in an un-debrickable state but I'll ask just in case. My phone is F800K.
I was toying around with LGUP in order to downgrade and root my phone. So far, so good.
I then tried to update to the latest android 9 again, but keep the root active. That's where things started to go south, so I decided to go back.
I followed a couple of "back to stock" guides but now I'm screwed.
- The phone does not boot.
- Download mode is broken, the phone doesn't connect to my computer while in download mode, so it's unusable.
- TWRP is gone. When I try to boot to recovery after yes both times I get nothing. Not the stock recovery and not TWRP, it just tries to boot as usual.
- Can't seem to go back into fastboot either. I tried VOLDOWN + plug-in the phone about 200 times now, to no avail.
Is there another way that I'm missing ?
Thanks.
Click to expand...
Click to collapse
It does sound like a hard brick... you said fastboot is hosed, do you have access to adb in any way?
Sent from my moto g(6) play using Tapatalk

None that I know of, that's the issue. If I had access to either fastboot, adb or download mode, I could most likely salvage this, but I can't seem to be able to.
The weirdest thing is the broken download mode, I couldn't find anybody with the same issue...

growiel said:
None that I know of, that's the issue. If I had access to either fastboot, adb or download mode, I could most likely salvage this, but I can't seem to be able to.
The weirdest thing is the broken download mode, I couldn't find anybody with the same issue...
Click to expand...
Click to collapse
On my lg tribute HD (ls676) fastboot was removed by lg themselves on Android 6.0.1 quietly with a security update and download mode never worked right for me. Without access to fastboot, adb or even diag mode it really sounds like you have a hard brick. if i can find a solution of some kind, I'll definitely let you know.
Sent from my moto g(6) play using Tapatalk

What would "diag mode" be and how can I check if I can access it ?

Small update for people who stumble upon this thread, I managed to save my phone by using the Qualcomm Test Point, see here: https://forum.xda-developers.com/showpost.php?p=81697447&postcount=128

Samsung Galaxy Tab A 8.0 SM-T290 2019, unable to unlock bootloader

Can anyone with this device provide the exact steps to unlock the bootloader. I have tried the many ways offered via google search and none seem to work. I have USB debugging and OEM unlock allowed in the device settings. I can boot into the bootloader via keys and using ADB. I've tried various key combos to get to the page (supposedly available) that allows one to switch the bootloader from locked to unlocked - no luck.
All help appreciated.

Do you mean that the command fastboot oem unlock doesn't work?
Note that: Unlocking bootloader wipes all device's data!

XDHx86 said:
Do you mean that the command fastboot oem unlock doesn't work?
Note that: Unlocking bootloader wipes all device's data!
Click to expand...
Click to collapse
Thanks for your reply and new suggestion. No that does not work either. I go to bootloader download mode, enter the command "fastboot oem unlock" and get "waiting on device". I am connected to the device as I get a response when queried "adb devices". Any other thoughts/suggestions?

[email protected] said:
Thanks for your reply and new suggestion. No that does not work either. I go to bootloader download mode, enter the command "fastboot oem unlock" and get "waiting on device". I am connected to the device as I get a response when queried "adb devices". Any other thoughts/suggestions?
Click to expand...
Click to collapse
You're supposed to boot the device to fastboot/bootloader by adb reboot bootloader not download mode.
Also to detect the device in fastboot the command is fastboot devices
Please if you're new to this stuff then don't do it. May I ask why you're trying to unlock bootloader?

XDHx86 said:
You're supposed to boot the device to fastboot/bootloader by adb reboot bootloader not download mode.
Also to detect the device in fastboot the command is fastboot devices
Please if you're new to this stuff then don't do it. May I ask why you're trying to unlock bootloader?
Click to expand...
Click to collapse
Again, thanks for your reply. I have previously installed Lineage on a Fire HD8. So not quite a newbie but everyone is new once - right? I am trying to install Lineage on this SM-T290.
The command "fastboot devices" is not returning anything but "adb devices" does which leads me to believe my hardware connections are correct. "adb reboot bootloader" does take me to the bootloader but it indicates download mode.
I suspect I am missing something simple. Your help is appreciated. Thanks

You need to enable OEM unlock and debugging mode first. And make sure the PC is allowed to debug on your phone.
Also if fastboot command doesn't return anything then most likely you need the correct device driver, you can get it from here.
Alternatively you can try this method:
Boot to download mode.
Long press volume up. This will wipe your data and automatically reboot.
After reboot you should have unlocked bootloader and OEM unlock option greyed out in the settings.
Installing custom ROM doesn't make your device better.

XDHx86 said:
You need to enable OEM unlock and debugging mode first. And make sure the PC is allowed to debug on your phone.
Also if fastboot command doesn't return anything then most likely you need the correct device driver, you can get it from here.
Alternatively you can try this method:
Boot to download mode.
Long press volume up. This will wipe your data and automatically reboot.
After reboot you should have unlocked bootloader and OEM unlock option greyed out in the settings.
Installing custom ROM doesn't make your device better.
Click to expand...
Click to collapse
Thanks but still no go.
I have enabled usb debugging and enabled OEM unlock (both done previously)
I have (had) installed latest drivers previously
adb devices returns my unit data
adb reboot bootloader command puts device in "download mode !!"
fastboot devices returns "waiting on device"
fastboot oem unlock also returns "waiting on device"
Attempted your alternative method, no go
I understand custom ROM doesn't make device better. I like the learning challenge. Hope you understand. Appreciate your help thus far and any other ideas you might have.

This is 100% driver issue, I already provided the driver link.
The device driver may be different from internet provided driver through windows device manager. Or the driver installed upon connecting the device.

XDHx86 said:
This is 100% driver issue, I already provided the driver link.
The device driver may be different from internet provided driver through windows device manager. Or the driver installed upon connecting the device.
Click to expand...
Click to collapse
Thanks. I had installed a driver from the link you supplied (there were a few options). I'll try others. I appreciate all your help!

Here's how I did it.
Enable Developer mode, usb debug, OEM unlock (you've already done those, by the sound of things).
Power the tablet OFF.
Have your USB cable plugged into the computer but NOT the tablet.
Hold the volume up AND volume down keys simultaneously, then connect the USB cable.
The tablet will vibrate and show a blue-green screen, with Warning at the top and a white triangle with an exclamation mark at the bottom. (This is different from download mode.)
From here, long-press volume up to go into device unlock mode. Follow the instructions.

Heeni said:
Here's how I did it.
Enable Developer mode, usb debug, OEM unlock (you've already done those, by the sound of things).
Power the tablet OFF.
Have your USB cable plugged into the computer but NOT the tablet.
Hold the volume up AND volume down keys simultaneously, then connect the USB cable.
The tablet will vibrate and show a blue-green screen, with Warning at the top and a white triangle with an exclamation mark at the bottom. (This is different from download mode.)
From here, long-press volume up to go into device unlock mode. Follow the instructions.
Click to expand...
Click to collapse
Thanks again but no luck. Let's start with some basics:
My device is a Galaxy Tab A SM-T290 8.0 2019 one UA core version 2.1
Android 10
When I, with power off, press both UP & DOWN volume keys simultaneously, wait a few seconds, insert the USB cable (already in computer), I get a vibration but then a circle with a lightning bolt that shows the battery charge status. The screen does not go blue-green and there is no warning.
I have tried releasing the buttons after the vibration and after I see the battery power circle. No change.
I continue to appreciate your help but feel I am missing something simple or my device is not same as yours.
Let me know if you have given up!

[email protected] said:
Thanks again but no luck. Let's start with some basics:
My device is a Galaxy Tab A SM-T290 8.0 2019 one UA core version 2.1
Android 10
When I, with power off, press both UP & DOWN volume keys simultaneously, wait a few seconds, insert the USB cable (already in computer), I get a vibration but then a circle with a lightning bolt that shows the battery charge status. The screen does not go blue-green and there is no warning.
I have tried releasing the buttons after the vibration and after I see the battery power circle. No change.
I continue to appreciate your help but feel I am missing something simple or my device is not same as yours.
Let me know if you have given up!
Click to expand...
Click to collapse
I see that your tablet has One UA core.
That may make a difference. I can't remember now where I saw it (somewhere on these forums), but I recall seeing that One UI Core is more locked down than the "ordinary" One UI version. Incidentally, I get the same response as you if I plug the tablet into a charger (not computer) while pressing both volume keys.
I'll mention at this point that I'm on the point of going back to stock and relocking the bootloader, because I've not been able to have a custom ROM or recovery and a screenlock (PIN, password, or pattern) at the same time, and no one seems to know any workaround for this. I'm starting to wonder if my tablet is somehow odd.
It's a nice piece of hardware, but a right pain to do any mods to, and Samsung's extra security "features" can cause problems.

Heeni said:
I see that your tablet has One UA core.
That may make a difference. I can't remember now where I saw it (somewhere on these forums), but I recall seeing that One UI Core is more locked down than the "ordinary" One UI version. Incidentally, I get the same response as you if I plug the tablet into a charger (not computer) while pressing both volume keys.
I'll mention at this point that I'm on the point of going back to stock and relocking the bootloader, because I've not been able to have a custom ROM or recovery and a screenlock (PIN, password, or pattern) at the same time, and no one seems to know any workaround for this. I'm starting to wonder if my tablet is somehow odd.
It's a nice piece of hardware, but a right pain to do any mods to, and Samsung's extra security "features" can cause problems.
Click to expand...
Click to collapse
Hey! Once again want to thank you for hangin' in with me on this. So, it seems we have slightly different machines. I purchased mine at COSTCO. They offer a lot of good stuff at low prices. I've noticed, however, they tweak their offerings a little bit so they can honestly say "you can't get this somewhere else." Perhaps the difference in our machines explains that.
I definitely had my unit plugged into the USB port on my computer, not a power supply.
My only purpose in attempting this was the satisfaction of doing it and having two tablets with different operating systems.
Thanks again for your help. All the best!

Here's the reference to One UI Core that I was thinking of: https://forum.xda-developers.com/t/root-for-sm-t290-tab-a-8-0-2019.3965624/post-84355183
I'm not based in North America, and the local market isn't big enough to have retailer-specific variants (or, at least, I've never heard of any), so I probably have a standard item. But from what I've read, specially locked-down items are reasonably common in the US. Which doesn't make it any less frustrating.

Heeni said:
Here's the reference to One UI Core that I was thinking of: https://forum.xda-developers.com/t/root-for-sm-t290-tab-a-8-0-2019.3965624/post-84355183
I'm not based in North America, and the local market isn't big enough to have retailer-specific variants (or, at least, I've never heard of any), so I probably have a standard item. But from what I've read, specially locked-down items are reasonably common in the US. Which doesn't make it any less frustrating.
Click to expand...
Click to collapse
I read the post and tried the extra step of holding the up volume key when the power screen came on. It also didn't work. Unless something new shows up, my quest to unlock this bootlocker is over. I'll find some other technical challenge to chase.
I had the thought of contacting Samsung to see if they would tell me how to do this. My unit is well out of warranty so why should they care? Likely they wouldn't tell me anything but .....
I'm on Denver CO. Where are you? In my work and fun travels I've had the opportunity to visit many parts of the world. Perhaps I've been to your country?
Again thanks for all your help. I could not have gotten as far as I did without it.

I'm in Auckland, New Zealand. It's a good place to live but not if you want cheap tech. Freight costs tend to be high.

Heeni said:
I'm in Auckland, New Zealand. It's a good place to live but not if you want cheap tech. Freight costs tend to be high.
Click to expand...
Click to collapse
Never been to New Zealand. On the bucket list as it seems a beautiful place to live. Been to your close neighbor Austrailia a number of times. Want to go there again to snorkel on the barrier reef. All the best!

[email protected] said:
I read the post and tried the extra step of holding the up volume key when the power screen came on. It also didn't work. Unless something new shows up, my quest to unlock this bootlocker is over. I'll find some other technical challenge to chase.
I had the thought of contacting Samsung to see if they would tell me how to do this. My unit is well out of warranty so why should they care? Likely they wouldn't tell me anything but .....
I'm on Denver CO. Where are you? In my work and fun travels I've had the opportunity to visit many parts of the world. Perhaps I've been to your country?
Again thanks for all your help. I could not have gotten as far as I did without it.
Click to expand...
Click to collapse
Try method below. It worked for me.
Root for SM-T290 (tab a 8.0 2019)
Hi guys, I just bought an SM-T290 for my wife and I was unable to find any info here about rooting it. As most Tab-A tablets "are here", can I use a guide (and twrp) for an older tablet for this newer model?
forum.xda-developers.com

bignikescar said:
Try method below. It worked for me.
Root for SM-T290 (tab a 8.0 2019)
Hi guys, I just bought an SM-T290 for my wife and I was unable to find any info here about rooting it. As most Tab-A tablets "are here", can I use a guide (and twrp) for an older tablet for this newer model?
forum.xda-developers.com
Click to expand...
Click to collapse
Holding vol up and down, with the tablet off, and plugging in the USB from PC to tablet, works. And it makes no difference which end of the cable you plug in last, so long as the buttons are already pressed before both ends are attached.

XDHx86 said:
Do you mean that the command fastboot oem unlock doesn't work?
Note that: Unlocking bootloader wipes all device's data!
Click to expand...
Click to collapse
You do not need a PC to unlock the bootloader. Turn off the device, then you will want to do Volume Up + Volume Down + USB Cable, and then Long Press Volume Up, and then press Volume Up again.

Samsung S10 + bootloop ERASE FAIL: READ ONLY

Samsung S10 + SM-F975F/DS IMEI stating Taiwan (Update: Very contradicting information if the phone is Snapdragon OR Exynos) if it even matters to solve the issue I dont know
Owner of the above since 2019 without issues; USB debugging mode activated in 2019 and never changed since then.
Samsung always updated which I assume the UI 3 Android got updated in January of my vague memory/recollection (honestly never paid attention of what is being updated, only that the phone needs to be on charge while doing ANY update)
Issue: phone in constant bootloop every 4 minutes with top message in red color "ERASE FAIL: READ ONLY" see photo attached
Cause: happened 4 days ago: Watched video stream on chrome browser; phone froze and applied a 10sec. power shut off (never had to do that before, 1st time)
Investigation:
I tried (found out by doing so) to interrupt the bootloop with pressing Power button and same time Volume Down Button in order to restart it and follow the following commands found on the internet as per UI 3 update:
Recovery Mode as followed does nothing:
Hold the Power button of your device till the power menu pops up and select Power Off. = does not apply as in bootloop
Wait for your device to turn off completely. = it does never turn off completely UNLESS I press Power button and same time Volume Down Button und plug into USB C Data cable of which the charging circle with the lightening strike appears without any percentage % of which photo is attached (phone charge can keep up with its bootloop in order to avoid battery drainage as there is no % indication)
Plug-in a USB-C data cable connected to your PC or USB-C earphones in your device. = I start from here whenever the phone restarts every 4 minutes or whenever I do it manually by pressing the buttons as I described in point 2.
Now, check if your device has a Bixby Button (Such as Galaxy S10/Note10):
Without Bixby Button: Press Volume Up + Power Button for a few seconds.
With Bixby Button: Press Volume Up + Bixby Button + Power Button for a few seconds
After the above steps, you will boot into Recovery mode.
Download Mode as followed does nothing: IT DOES WORK NOW you need to be very fast before the phone starts (recovery mode does not work)
Make sure you have a USB cable connected to the computer
Then press and hold the Volume Down and Bixby buttons at the same time
Continue holding these two buttons down while you insert the USB cable that is connected to the PC
Recovery Mode before update instructions as followed does nothing:
Step 1: Start by turning off your Galaxy S10.
Step 2: After it’s powered down, press and hold Volume Up button and Bixby button (this is the button underneath the volume buttons in case you didn’t know).
Step 3: Without letting go of the Volume Up and Bixby buttons, press and hold the Power button.
Step 4: As soon as your device turns on, let go of the Power button.
Step 5: After you see a blue screen, let go of the remaining two buttons. Now you are in Recovery mode.
Download Mode before update instructions as followed does nothing:
Step 1: Turn off your Galaxy S10.
Step 2: When it’s turned off, press and hold the Volume Down button and Bixby button.
Step 3: Without letting go of the two buttons, press and hold the Power button.
Step 4: You will get into Download Mode.
Have tried all the above methods several times the past 4 days.
Have drained the battery in terms of keeping the phone in bootloop resulting in no power.
Unhooked the battery by means of removing the rear panel and unhooking the battery cable for more then 15minutes and repeat the 4 different methods
Unhooked the mainboard from various connections and put together and repeat the 4 different methods
No indications in Windows 10 Device manager
Questions, doubts and thoughts:
Is it possible in this state to access with ADB of a professional in order to perhaps clear the cache, resolve the issue without having access to recovery mode?
Should I simply try to purchase a new battery even though I never had any battery issues?
I am aware that a motherboard change will resolve it to the cheapest way possible but as I like to save the data such as different accounts this is not an option besides the phone is physically in good condition (never went under water or dropped). maybe to unsolder the flash memory onto a new mainboard as recovery mode might be part of the processor where the RAM is saved.
Any way to drain the entire phone further which may resolve the issue without loosing data. Similar in removing a CMOS battery on a PC mainboard and using a jumper.
Willing to pay and currently living in Europe.
UPDATE: Odin firmware performed by skilled professional member of xda forum, but still not working. EMMC issue which needs to be addressed with ISP in order to fix the issue. unfortunately I was told by local professionals that they do not have the tools for it. Therefor I wonder if someone knows someone who knows someone who can be of help. Location is Spain but Europe would also work.
UPDATE2: Got the phone back from technician who has experience with ISP but still same Error remains as to his conclusion that this is not an Exynos phone of which he has not the hardware tool to fix it and probably no one in Europe will have it.
Thank you very much in advance

Sorry... my english not so good...
so the point is whether you can enter recovery or download mode or not ?

Vuska said:
Sorry... my english not so good...
so the point is whether you can enter recovery or download mode or not ?
Click to expand...
Click to collapse
I am able now to enter download mode.

snakebite3 said:
I am able now to enter download mode.
Click to expand...
Click to collapse
and do you able to flash stock again ? (newest one, because we cant downgrade the bootloader)...

Vuska said:
and do you able to flash stock again ? (newest one, because we cant downgrade the bootloader)...
Click to expand...
Click to collapse
Thank you for following up.
these ones were tried out:
Samfw.com_SM-G975F_DBT_G975FXXS9DTI8_fac
Samfw.com_SM-G975F_DBT_G975FXXU9FUCD_fac
Samfw.com_SM-G975F_XSG_G975FXXU9FUBD_fac
I am not sure but that person who helped me remotely may explain better

According to technician its Qualcomm Snapdragon which can only be fixed with the right tools. Not in europe.
I been getting different information and do require some expertise if someone can please help me

any further advice, input or suggestion?

I also Own Samsung S10+.
its showing the same thing.
tried Flashing Via Odin it failed.
Tried to enter Recovery Mode but also failed to enter recovery mode.

OMG. I thought I was the only one in the world. I sent it yesterday to a data recovery technician to see what they will do since according to some insider in order to recover the data they would have to access the phone and fix the boot of which the problem get solved itself since they can not remove the memory chip itself as it would get ruined. They will diagnose the problem first before they do anything. Obviously a mainboard change would be the easiest but thats not an option.
Was your phone also updated to UI Android 3.0?
How did it happen if I may ask?
I wont give up since my phone is physically totally fine.

Update from a data recovery company its communication:
What we tried to do in order to recover your device's data was to load through the phone's bootloader (in Download Mode) a software agent that allows us (in some cases) to transfer the data stored in the data partition. This software agent has been developed by us together with some of our partners and as we are sure you will understand we cannot give you more details about what this particular software does or how it does it, since this information is covered by professional and business secrecy.
In this case the phone's firmware was damaged to a degree that made it impossible for the information to be accessed with this software.
At this moment, we doubt the data could be recovered by any software available now in the market. That's our opinion, but you can of course send it to other companies to see if they can recover it.
Since I am not the only one anymore with the same issue I recommend for people to come forward in order to get help

So far there is a tool needed to reprogram EMMC but I dont know which tool neither do I know where to find that person with this knowledge

snakebite3 said:
So far there is a tool needed to reprogram EMMC but I dont know which tool neither do I know where to find that person with this knowledge
Click to expand...
Click to collapse
Your device is powered by Snapdragon or Exynos?

LinhBT said:
Your device is powered by Snapdragon or Exynos?
Click to expand...
Click to collapse
I honestly dont know anymore since numerous people said contradicting things.
I am under the impression it is Exynos as of the research of the model SM-G975F/DS

Need to know exactly if it's Snap or not. If it is, then there're 2 options you can try.
1. Ask some one have the same device model as you, do a ROM dump ( you can google for more detail ). Once you got that, I can share with you the tool needed for restore your device from that dump.
2. Try find your device's Factory Images ( similar to Fastboot ROM, but a little different ), and an authenticated prog of your SoC ( this I can share too if you choose this option ) then boot your device into EDL mode by using fastboot2EDL script ( on Git, you can google too ) then use QFIL ( one tool in QPST Tools by Qualcomm ) and force flash the images into the device.
So far as my experience and understanding, there're only these 2 solutions to fix your device ( if it's Snap powered ).

According to the seller: "The phone is Taiwanese version and CPU should be Exynos 9820"
Maybe someone can help me please.. still

If its Exynos powered, then I have no solution for it. Sorry bro!!!

LinhBT said:
If its Exynos powered, then I have no solution for it. Sorry bro!!!
Click to expand...
Click to collapse
Thank you for your reply.
Can you please explain me why and who I should be looking for.

Anyone has knowledge how to fix this issue, please? USA based

LinhBT said:
Need to know exactly if it's Snap or not. If it is, then there're 2 options you can try.
1. Ask some one have the same device model as you, do a ROM dump ( you can google for more detail ). Once you got that, I can share with you the tool needed for restore your device from that dump.
2. Try find your device's Factory Images ( similar to Fastboot ROM, but a little different ), and an authenticated prog of your SoC ( this I can share too if you choose this option ) then boot your device into EDL mode by using fastboot2EDL script ( on Git, you can google too ) then use QFIL ( one tool in QPST Tools by Qualcomm ) and force flash the images into the device.
So far as my experience and understanding, there're only these 2 solutions to fix your device ( if it's Snap powered ).
Click to expand...
Click to collapse
Hi mate, My phone is Snapdragon powered..
My problem is almost similar.. But not exactly.. After almost 2 months I am not able to find a solution.. But after this period of researching and googling about things related to my problem.. I feel now, either any one of the following is the cause of problem:
1. Emmc is stuck or locked in read-only mode `(Can move files from pc , delete already present files anywhere in any directory, but all changes vanish after reboot... all file and directory structure remain intact- moved files from pc gets deleted.. and deleted files which were already present come back after reboot )
2. Corrupted /data and /cache partition, as e2fsck in twrp terminal results shows "filesystem still has errors" and "e2fsck: unable to set superblock flags on /dev/block/mmcblk0p** ) in both these file system (I think they are preventing flashing procedures- Odin stock firmware flashes and twrp custom ROM flashes both are successful, but after reboot no changes can be seen... - Even Recovery.img and boot.img flashes don't seem to work even both are shown successfully flashed in twrp) After reboot current version twrp boots again instead of newly flashed different version recovery.img ... same with boot.img even after running magisk uninstaller zip files.. running uninstall.zip 2nd or 3rd time also shows magisk patched image detected in log which should be removed in 1st iteration itself..
3. Might be magisk is preventing these changes to be made.. or It might be the /System_root creation as mountpoint for system partition which used to be previously /system normally. This might be the superblock creation which not used to be there
My Samsung's twrp and Download Mode seems to be working but no changes made by them even after successful operations by both.
Can you suggest anything? You can look my thread as to get even more detailed overview of what's happening and whatever I'have tried here - https://forum.xda-developers.com/t/...t-not-changing-anything-after-reboot.4462639/
You can see my attachments in my above thread to see my directory structure of system_root and my download mode pictures and odin system ROM flash pictures.

LinhBT said:
Need to know exactly if it's Snap or not. If it is, then there're 2 options you can try.
1. Ask some one have the same device model as you, do a ROM dump ( you can google for more detail ). Once you got that, I can share with you the tool needed for restore your device from that dump.
2. Try find your device's Factory Images ( similar to Fastboot ROM, but a little different ), and an authenticated prog of your SoC ( this I can share too if you choose this option ) then boot your device into EDL mode by using fastboot2EDL script ( on Git, you can google too ) then use QFIL ( one tool in QPST Tools by Qualcomm ) and force flash the images into the device.
So far as my experience and understanding, there're only these 2 solutions to fix your device ( if it's Snap powered ).
Click to expand...
Click to collapse
any tips here?
S20 FE bootloop after security update
So I never posted here but I usually pass by some topics so sorry for any mistake in creating this discussion. Today I deleted some stuff from my S20 FE and downloaded via OTA the march security update in my device, then I was caught by surprise...
forum.xda-developers.com

Lenovo Tab M10 FHD Plus (X606f) won't power on after flashing older ROM

I'm flashing my new Lenovo tablet with Android 9 (so I can flash it later with Ubuntu Touch) and after SP Flash tool finished flashing
tablet won't power on. The power button does nothing and holding volume down + power button does nothing either.
The battery isn't dead so I'm trying to figure out why the tablet won't come on if older ROM is on it.
I had no error outputs during the flash.
This is the ROM I flashed https://mirrors.lolinet.com/firmwar..._Gen/TB-X606F/TB-X606F_S300007_200923_BMP.zip
Any suggestion as to how to get it to work again ?

I don't think you can downgrade these. You may need to completely wipe and reinstall the ROM.

ldeveraux said:
I don't think you can downgrade these. You may need to completely wipe and reinstall the ROM.
Click to expand...
Click to collapse
I'm using the official Lenovo's Rescue Tool but it's not helping. The tool isn't detecting the device after holding volume up + connecting.

python_rocks said:
I'm using the official Lenovo's Rescue Tool but it's not helping. The tool isn't detecting the device after holding volume up + connecting.
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assuming windows, check that your drivers are detecting the recovery module

ldeveraux said:
assuming windows, check that your drivers are detecting the recovery module
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Yes I'm using W10. adb is working and I've got Lenovo USB drivers installed too. What do you mean by "recovery module" ? Recovery partition inside the tablet ?

python_rocks said:
I'm flashing my new Lenovo tablet with Android 9 (so I can flash it later with Ubuntu Touch)...
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Cool. Are you doing a Halium port for this device?

Yahoo Mike said:
Cool. Are you doing a Halium port for this device?
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I'm not a Halium dev but I'm trying to flash the device. Me and another member of the community have our tablets dead after flushing it with supposedly Android 9 ROM. Not even Lenovo's Rescue Tool is helping now.

python_rocks said:
Yes I'm using W10. adb is working and I've got Lenovo USB drivers installed too. What do you mean by "recovery module" ? Recovery partition inside the tablet ?
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Click to collapse
No i mean when you connect the tablet to the pc in recovery, open Device Manager and ensure the tablet is connected with the correct driver. I'm sorry i don't know what that is offhand, but it should be different than when you connect it if the tablet was working. Sorry if it makes no sense, but i think this is what's going on.

ldeveraux said:
No i mean when you connect the tablet to the pc in recovery, open Device Manager and ensure the tablet is connected with the correct driver. I'm sorry i don't know what that is offhand, but it should be different than when you connect it if the tablet was working. Sorry if it makes no sense, but i think this is what's going on.
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In my case there's no "connect the tablet to the PC in recovery". The tablet won't power on at all. Can't invoke fastboot nor recovery. The tablet doesn't react to any presses. Or press and holds. No nothing. The only thing I can confirm is the red LED on when the tablet is on charger.
Window's device manager is recognizing MediaTek USB driver when plugged in but that's it.
I've ran out of ideas about how to restore it hence I'm posting here.

python_rocks said:
In my case there's no "connect the tablet to the PC in recovery". The tablet won't power on at all. Can't invoke fastboot nor recovery. The tablet doesn't react to any presses. Or press and holds. No nothing. The only thing I can confirm is the red LED on when the tablet is on charger.
Window's device manager is recognizing MediaTek USB driver when plugged in but that's it.
I've ran out of ideas about how to restore it hence I'm posting here.
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Oh i misunderstood completely! That is worse, i have no clue how to fix it...

python_rocks said:
The tablet won't power on at all.
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If it's that dead, then it sounds like the preloader.bin is trashed.
Try this method.
There is also an older thread for older SOCs that might have some hints.
Otherwise, you might have to open up the tablet.
You could research and try the "test point" method. It involves shorting two points on the motherboard. I did something similar for the X605F (which has a QCom SOC).
I'm not sure where the test points on this tablet are. Some MTK devices don't have test points. Google "mediatek test point" for starters. If you can't find them, then maybe ask Lenovo where they are. If you find out, post a photo of the test points on here.
If you're not confident doing any of this, then send the tablet to Lenovo for repair.

Yahoo Mike said:
If it's that dead, then it sounds like the preloader.bin is trashed.
Try this method.
There is also an older thread for older SOCs that might have some hints.
Otherwise, you might have to open up the tablet.
You could research and try the "test point" method. It involves shorting two points on the motherboard. I did something similar for the X605F (which has a QCom SOC).
I'm not sure where the test points on this tablet are. Some MTK devices don't have test points. Google "mediatek test point" for starters. If you can't find them, then maybe ask Lenovo where they are. If you find out, post a photo of the test points on here.
If you're not confident doing any of this, then send the tablet to Lenovo for repair.
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Click to collapse
Yeah, I've ordered opening kit. I'm going in. Quite a few people got their devices working by disconnecting the battery and connecting it back. I've noticed that no matter how long the
tablet is on charger the LED stays red, it doesn't change to orange or green.
This same problem has happen to two more members of the community. Same tablet.
We had to flag that ROM as it bricks the tablet.

python_rocks said:
We had to flag that ROM as it bricks the tablet.
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I don't have a lot of experience with the SPF tool, but could the root-cause of your problem be that you need to use a different dropdown option? See the description of the options in the unbrick guide - specifically the firmware upgrade option.
It makes sense that you want to force a full flash of low-level firmware when changing Android versions. That option seems to do exactly that.
Android 9 OS is not going to play nice with low-level firmware written for Android 10.
There might be nothing wrong with the ROM ??? ...just an idle thought.

Yahoo Mike said:
I don't have a lot of experience with the SPF tool, but could the root-cause of your problem be that you need to use a different dropdown option? See the description of the options in the unbrick guide - specifically the firmware upgrade option.
It makes sense that you want to force a full flash of low-level firmware when changing Android versions. That option seems to do exactly that.
Android 9 OS is not going to play nice with low-level firmware written for Android 10.
There might be nothing wrong with the ROM ??? ...just an idle thought.
Click to expand...
Click to collapse
Thank you for trying to help.
The flash tool doesn't do anything when I click Download and plugging in the tablet while holding the volume down button. Dropdown option was set to "firmware upgrade" as advised.
The guide suggests that it's for people who can at least power on the device. It says "switch off the phone ..." which I don't need to do since I can't even switch it on

python_rocks said:
I'm flashing my new Lenovo tablet with Android 9 (so I can flash it later with Ubuntu Touch) and after SP Flash tool finished flashing
tablet won't power on. The power button does nothing and holding volume down + power button does nothing either.
The battery isn't dead so I'm trying to figure out why the tablet won't come on if older ROM is on it.
I had no error outputs during the flash.
This is the ROM I flashed https://mirrors.lolinet.com/firmwar..._Gen/TB-X606F/TB-X606F_S300007_200923_BMP.zip
Any suggestion as to how to get it to work again
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Did you mange to fix it?

A. Alaska said:
Did you mange to fix it?
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You need to use a rework station heat gun or maybe a hair blow dryer might work to heat the sides of the screen to remove it.
I recommend cutting a water bottle in a square or rectangle shape then using the corner to slowly pry the screen off. After that remove the battery ribbon and hold the power bottom for 20-60 seconds to fully drain the charge.
Then recconect it and turn it on 100 percent works.
Just remember you must have the flash tool app and firmware ready in upgrade or download mode while holding down vol. It will reflash the tablet and bam will unbrick.

Just to note down my experiences here as well. I now also got into the same trouble. I tried
TB-X606F_S100015_191127_BMP.zip and also TB-X606F_S300091_201215_BMP.zip
It turns out that with these two you cannot start up the device anymore. Just as the thread-creator described. In my case pluging out and in again seems to give the SP FalshTool the chance to flash again (put it in "Download"-Mode before). So the latest firmware by today - TB-X606F_S300429_21110_BMP.zip - helped me to revive it again.
For me this is nice, but I also wanted to put Ubuntu touch on it just as described here: https://gitlab.com/ubports/community-ports/android9/lenovo-tab-m10-fhd-plus/lenovo-x606 ... unfortunately I am blocked now due to not being able to bring Android 9 on it. btw: There is no proposal on the site which firmware-version is even Android 9. I just guessed from the date.

ROOT SM-T555 Nougat (Android 7.1.1)

Hello...
I am looking for a working way to root my SM-T555
The device is running android 7.1.1;
base ver. "T555XXU1CQHA";
build ver. "NMF26X.T555XXU1CRG1";
Samsung experience 8.5;
Android security patch August 2017.
So far, the several attempts I made using every T55X related software I found in this website have been unsuccessful.
It would seem that the rooting software available is for "Marshmallow only", thus not Nougat specific,
though I read some comments stating that the TWRP made for MM worked on Nougat too and, after that, Magisk would/could do the job...
So I gave it a try but, after installing the recovery, my tablet got stuck every time: refused to boot normally
and if I turned it off, long pressing the power key, I couldn't turn it on again as if it was bricked.
Every time I had to re-start it in download mode and re-flash the original stock rom with Odin in order to have it working again.
On top of that, the "OEM unlock" key is not present in the developer mode list: none of the "date changing tricks" I found around the web seems to fit this model.
I am inclined to believe this "might" be the mother of my problems in rooting the device though, supposedly, the patches were not for Nougat, anyway...
The developer options page, once activated, can only be "turned off" ("greyed out") but cannot be deactivated;
while, on other devices, if you turn it off the page usually disappears after rebooting then you have to tap 7 times the build version, again, in order to make it appear.
I never had problems in rooting any of the phones and tablets I have /had, including an SM-T819 running Nougat 7.1.1,
thanks to the great job done by the coders in this community to whom I would like to express my appreciation for what they do for the benefit of us all.
But this thing seems to reject everything I throw at it and it's been the most stubborn "phone like object" I ever fought with.
So far I am the one loosing the fight... I wish some of you guys could give me the means to defeat it.
Thanks in advance to whoever may be available to help me out.

Flash TWRP, then install Magisk in TWRP.

V0latyle said:
Flash TWRP, then install Magisk in TWRP.
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thanks for your reply.
maybe my post was too long and boring so you didn't read it all
Of course I already tried the solutions posted in the page you suggested but they did not work.
not the autoroot files, not the recovery, etc...
I quote: "after installing the recovery, my tablet got stuck every time: refused to boot normally
and if I turned it off, long pressing the power key, I couldn't turn it on again as if it was bricked.
Every time I had to re-start it in download mode and re-flash the original stock rom with Odin in order to have it working again."
If there is a TWRP file specific for my Nougat version available I'd be happy to give it a shot

endlessquest said:
thanks for your reply.
maybe my post was too long and boring so you didn't read it all
Of course I already tried the solutions posted in the page you suggested but they did not work.
not the autoroot files, not the recovery, etc...
I quote: "after installing the recovery, my tablet got stuck every time: refused to boot normally
and if I turned it off, long pressing the power key, I couldn't turn it on again as if it was bricked.
Every time I had to re-start it in download mode and re-flash the original stock rom with Odin in order to have it working again."
If there is a TWRP file specific for my Nougat version available I'd be happy to give it a shot
Click to expand...
Click to collapse
Did you follow a guide when flashing TWRP? Did you unlock your bootloader?
You need to be clear and concise in your posts as yo what you did and how.

V0latyle said:
Did you follow a guide when flashing TWRP? Did you unlock your bootloader?
You need to be clear and concise in your posts as yo what you did and how.
Click to expand...
Click to collapse
of course I did follow the guide by the book. also, the recovery appears to be installed properly, Odin showing a nice green PASS sign, but it doesn't work anyway
now about unlocking the bootloader, as I mentioned in my first post:
"the "OEM unlock" key is not present in the developer mode list: none of the "date changing tricks" I found around the web seems to fit this model.
I am inclined to believe this "might" be the mother of my problems in rooting the device"
every time I had to re install the system, so there clock want back to zero. Maybe I should be waiting for the allotted number of days to pass on order for the OEM unlock key to appear...
but before my first attempt to root the device, almost one month was past and the OEM unlock key wasn't there, notwithstanding...
I hope there was a chance that the bootloader was already unlocked...

to be concise (schematic):
tablet in download mode
untick auto reboot in Odin
AP loaded with "smt550_cf-autoroot.tar"
flash with Odin, OK, green sign PASS
reboot manually home+volume down+power,
then switch to volume up when screen becomes black
the Samsung logo appears and stays there indefinitely
So I turn the device off, long pressing the power key
then I try and turn on the tablet but does not turn on anymore,
not even pressing the power button for 30 second
then I press home+volume down+power again
to enter download mode and reinstall stock rom
(the same happens with
sm-t550_p550_p555_cf-autoroot.tar
or twrp_3.0.2-1_sm-t550_mm_7816.tar,
I also tried
twrp_3.1.1-1_sm-t355_251117
remark: none of them mentions T555 nougat)

Put your tablet in Download Mode and take a picture of the text at the upper left of the screen.

V0latyle said:
Put your tablet in Download Mode and take a picture of the text at the upper left of the screen.
Click to expand...
Click to collapse

What process did you follow to unlock your bootloader?
Stop trying to use Autoroot. Let's figure out what we need to do to get TWRP on your device. Once we do that, you can flash Magisk in TWRP for root.
Please read this guide, sections 1 through 4 (don't worry about the GSI stuff) and tell me what you have or have not done.

ok, I wasn't able to do this:
Unlock Bootloader
Enable Developer Options and turn on OEM Unlocking
OEM Unlocking is missing in the list, as I mentioned in my previous posts
I tried the date change trick but it didn't work

endlessquest said:
ok, I wasn't able to do this:
Unlock Bootloader
Enable Developer Options and turn on OEM Unlocking
OEM Unlocking is missing in the list, as I mentioned in my previous posts
I tried the date change trick but it didn't work
Click to expand...
Click to collapse
This is the first step. You cannot flash custom or modified images if the bootloader is locked.
Connect to the Internet and check for updates in system options, then check Developer Options again.

I did that step too, several times:
the system found an update available
the first times I cancelled the download
then I downloaded the update without installing it
then I tried and installed it
no result at all the attempts: the OEM Unlock key does not appear in developer options

endlessquest said:
I did that step too, several times:
the system found an update available
the first times I cancelled the download
then I downloaded the update without installing it
then I tried and installed it
no result at all the attempts: the OEM Unlock key does not appear in developer options
Click to expand...
Click to collapse
Has it ever appeared before?

V0latyle said:
Has it ever appeared before?
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Click to collapse
it is the first time I work on this specific device, so I couldn't tell: so far I couldn't find the OEM unlock option in the list
it never happened before on any of the several devices I have rooted in my life,
included another Samsung tablet SM-T819 running Nougat 7.1.1: the option was right there and all I had to do is tick it.
I used fastboot for other brands
I wish there was a way to use fastboot to unlock the bootloader on Samsung
if there is any I don't know it
adb is working, but when I give the "adb reboot fastboot" command, the tablet enters the download mode and fastboot does not see the tablet anymore from the computer

endlessquest said:
it is the first time I work on this specific device, so I couldn't tell: so far I couldn't find the OEM unlock option in the list
it never happened before on any of the several devices I have rooted in my life,
included another Samsung tablet SM-T819 running Nougat 7.1.1: the option was right there and all I had to do is tick it.
I used fastboot for other brands
I wish there was a way to use fastboot to unlock the bootloader on Samsung
if there is any I don't know it
adb is working, but when I give the "adb reboot fastboot" command, the tablet enters the download mode and fastboot does not see the tablet anymore from the computer
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Click to collapse
Samsung devices do not have a fastboot mode.
Since this is a Snapdragon device, it probably cannot be unlocked, especially if it was marketed in the US.
Only Exynos and international Snapdragon devices can be unlocked, unfortunately.

V0latyle said:
Samsung devices do not have a fastboot mode.
Since this is a Snapdragon device, it probably cannot be unlocked, especially if it was marketed in the US.
Only Exynos and international Snapdragon devices can be unlocked, unfortunately.
Click to expand...
Click to collapse
actually I am in Rome, Italy so I am quite positive it was marketed here...
is there a way to know for sure whether or not it is international?

the Samsung SM-T819 I am writing from has a snapdragon chip
but I had no problem unlocking/rooting it,
I bought both the devices here in Rome
now that's a mystery...

endlessquest said:
actually I am in Rome, Italy so I am quite positive it was marketed here...
is there a way to know for sure whether or not it is international?
Click to expand...
Click to collapse
Usually the model number is a good indication with phones - the G908U vs G908N for example, but I don't see that being the case here
Have you tried signing into a Samsung or Google account on the device before checking for updates and looking for OEM Unlocking?

V0latyle said:
Usually the model number is a good indication with phones - the G908U vs G908N for example, but I don't see that being the case here
Have you tried signing into a Samsung or Google account on the device before checking for updates and looking for OEM Unlocking?
Click to expand...
Click to collapse
I did that too...
on a freshly installed rom:
I connected the internet thru wireless
signed into my Google account
completed the tablet configuration, etc
then I went and enable the developer options
no OEM Unlocking yet again...

endlessquest said:
I did that too...
on a freshly installed rom:
I connected the internet thru wireless
signed into my Google account
completed the tablet configuration, etc
then I went and enable the developer options
no OEM Unlocking yet again...
Click to expand...
Click to collapse
You manually checked for an update too?
Did you try disconnecting from the Internet, disabling network time, and manually setting the time ahead 1 week?