Database Users

[TF300TG][Guide] Flashing back the original stock ROM

Hi everyone,
I'm owning A TF300TG model and I recently tried to flash one of the ROMS referrenced on those forums and by doing so I found out that my tablet had lost the 3G features so I had to flash back the Asus stock ROM to get it back.
Since I saw many of you got trouble reinstalling the stock ROM, I decided to write a quick guide on how to do it so everyone could get their tablet fully working again
Note: For the record, when I did the following operations, I already had unlocked the bootloader and installed the CWM recovery.
Disclaimer:
By following this guide, you will have to issue commands that risk to damage (aka. brick) your tablet or at least void your warranty. I won't be responsible for any damage made to your device. You've been warned.
Click to expand...
Click to collapse
Download the stock ROM zip file on Asus website (current version is [WW | TW]_epaduser9_4_4_28_1UpdateLauncher.zip) for the TF300TG tablet. Be sure to download the firmware matching your SKU.
Unzip the downloaded file, you will get another archive called , unzip this one too
You should end up with several file, with one of them called blob
For the next step, you will need to install the Android SDK to get the fastboot utility. If you do not know how to use fastboot, you should take a look at this guide.
Once you have installed fastboot, boot your tablet into fastboot mode (Plugin your tablet on your computer's USB, Hold down Power+VolDown, dont press VolUp when prompted, select the USB icon and press VolUp)
Open a command line terminal and navigate to the folder containing the blob file.
Then type the following command:
fastboot -i 0x0B05 flash system blob
Click to expand...
Click to collapse
For some reason, the transfer seems to fail from time to time, if so, just try again by going back to previous step.
Once the transfer is done and you get that sweet "SUCCESS" printed on your screen, just type the following command to reboot your tablet:
fastboot -i 0x0B05 reboot
Click to expand...
Click to collapse
And there you have ! You are now back to stock ROM with fully working 3G

Thanks a lot for this, I found these instructions on Wolf's thread but wasnt sure it would work with our devices, Thanks for taking the first big step.
Questions.
1. Does this wipe your data?
2. Does CWM still work after?

AFAIK, this will wipe your data, remove CWM and uninstall root. Your device's bootloader will still stay unlocked though.
You will have to flash CWM back using this guide: http://forum.xda-developers.com/showthread.php?t=1668173

Hi, followed the steps but it didnt work for me
Fastboot copies the file but after when it tries to flash it gives an error
sending 'system' (796653 KB)...
OKAY [137.443s]
writing 'system'...
FAILED (remote: ()
finished. total time: 138.477s
The Tab shows
Failed to process command flash:system error(0x170003)
The progress bar is showing under the USB logo with 1% blue, after hold power down I'm back into Onyx Rom
Any Thoughts?

I had the same problem and I just issued the same command a second time and it worked just fine
Try to format your /system (under the mounts and storage option) from CWM and wipe data and cache.

2nd time a charm!
Worked fine the second time i ran the command,
Im back to stock again :good:
I will wait for a 3G friendly Rom before flashing again
Thanks for your help
---------- Post added at 05:59 PM ---------- Previous post was at 05:42 PM ----------
Auliyaa said:
AFAIK, this will wipe your data, remove CWM and uninstall root. Your device's bootloader will still stay unlocked though.
You will have to flash CWM back using this guide: http://forum.xda-developers.com/showthread.php?t=1668173
Click to expand...
Click to collapse
Yip Sends you back to total stock
Stock Recovery
Stock Rom
only thing that sticks is Unlocked Bootloader

Thanks a million. This worked for me as well after 2 tries. Saved my $400!

Thanks heaps for this
I ended up in trouble when I flashed the TF300T firmware by mistake. It kept freezing and rebooting on me after that little stuff up.
Anyhow before I did that I made a backup with CWM, and after I restored it my 3G was gone but everything else worked fine.
Manual updates were failed though and they still do. At least I have my 3G back :victory:
So this method would probably work for upgrading to .40 as well, but it means a complete datawipe!
I'm sure there are many of us in the same boat now. I guess we will just have to wait and hope that some kind person makes a recovery image for the TF300TG?

Auliyaa said:
Hi everyone,
I'm owning A TF300TG model and I recently tried to flash one of the ROMS referrenced on those forums and by doing so I found out that my tablet had lost the 3G features so I had to flash back the Asus stock ROM to get it back.
Since I saw many of you got trouble reinstalling the stock ROM, I decided to write a quick guide on how to do it so everyone could get their tablet fully working again
Note: For the record, when I did the following operations, I already had unlocked the bootloader and installed the CWM recovery.
Download the stock ROM zip file on Asus website (current version is [WW | TW]_epaduser9_4_4_28_1UpdateLauncher.zip) for the TF300TG tablet. Be sure to download the firmware matching your SKU.
Unzip the downloaded file, you will get another archive called , unzip this one too
You should end up with several file, with one of them called blob
For the next step, you will need to install the Android SDK to get the fastboot utility. If you do not know how to use fastboot, you should take a look at this guide.
Once you have installed fastboot, boot your tablet into fastboot mode (Plugin your tablet on your computer's USB, Hold down Power+VolDown, dont press VolUp when prompted, select the USB icon and press VolUp)
Open a command line terminal and navigate to the folder containing the blob file.
Then type the following command:
For some reason, the transfer seems to fail from time to time, if so, just try again by going back to previous step.
Once the transfer is done and you get that sweet "SUCCESS" printed on your screen, just type the following command to reboot your tablet:
And there you have ! You are now back to stock ROM with fully working 3G
Click to expand...
Click to collapse
I got a question, i had problems with the touch since the last update, so i want to go back to the original, so my question is to perform this do i have to have the bootloader unlocked?

Auliyaa said:
Hi everyone,
[*] Once you have installed fastboot, boot your tablet into fastboot mode (Plugin your tablet on your computer's USB, Hold down Power+VolDown, dont press VolUp when prompted, select the USB icon and press VolUp)
Click to expand...
Click to collapse
Hi, any idea why i dont have this 'USB icon' ?? i have 'wipe data' and an android icon that performs a cold boot.

Any idea why this will seemingly flash fine, but go to bootloop when I fastboot -i 0x0b05 reboot the tab?

Don't work for me
Auliyaa said:
Hi everyone,
I'm owning A TF300TG model and I recently tried to flash one of the ROMS referrenced on those forums and by doing so I found out that my tablet had lost the 3G features so I had to flash back the Asus stock ROM to get it back.
Since I saw many of you got trouble reinstalling the stock ROM, I decided to write a quick guide on how to do it so everyone could get their tablet fully working again
Note: For the record, when I did the following operations, I already had unlocked the bootloader and installed the CWM recovery.
Download the stock ROM zip file on Asus website (current version is [WW | TW]_epaduser9_4_4_28_1UpdateLauncher.zip) for the TF300TG tablet. Be sure to download the firmware matching your SKU.
Unzip the downloaded file, you will get another archive called , unzip this one too
You should end up with several file, with one of them called blob
For the next step, you will need to install the Android SDK to get the fastboot utility. If you do not know how to use fastboot, you should take a look at this guide.
Once you have installed fastboot, boot your tablet into fastboot mode (Plugin your tablet on your computer's USB, Hold down Power+VolDown, dont press VolUp when prompted, select the USB icon and press VolUp)
Open a command line terminal and navigate to the folder containing the blob file.
Then type the following command:
For some reason, the transfer seems to fail from time to time, if so, just try again by going back to previous step.
Once the transfer is done and you get that sweet "SUCCESS" printed on your screen, just type the following command to reboot your tablet:
And there you have ! You are now back to stock ROM with fully working 3G
Click to expand...
Click to collapse
Hi, followed the steps but it didnt work for me too
Fastboot copies the file but after when it tries to flash it gives an error
sending 'system' (796581 KB)...
OKAY [129.964s]
writing 'system'...
FAILED (remote: (InvalidState))
finished. total time: 182.134s
The Tab shows
signature mismatch
Can you help me?

hy
i'm having a problem with my tf300t...when i turn it on it shows the asus logo and in the upper left it show device is unlocked...but i can't enter the menu showing rck and the other 3 icons...i really don't know what to do...
then there is another thing...tried to install driver...i get to the part where the tablet is visible, but with the vol up and reset with a pin...it then shuts down and if i try to power it up it dissapears from the device manager...also...if i don't turn it up, the driver can't be installed...i tried every method...please help...
can i retun it to the repair service this way or i will loose my waranty?
sorry if the spelling isn't correct...i don't speak english fluently
waiting a response...thanks in advance

Auliyaa said:
Hi everyone,
I'm owning A TF300TG model and I recently tried to flash one of the ROMS referrenced on those forums and by doing so I found out that my tablet had lost the 3G features so I had to flash back the Asus stock ROM to get it back.
Since I saw many of you got trouble reinstalling the stock ROM, I decided to write a quick guide on how to do it so everyone could get their tablet fully working again
Note: For the record, when I did the following operations, I already had unlocked the bootloader and installed the CWM recovery.
Download the stock ROM zip file on Asus website (current version is [WW | TW]_epaduser9_4_4_28_1UpdateLauncher.zip) for the TF300TG tablet. Be sure to download the firmware matching your SKU.
Unzip the downloaded file, you will get another archive called , unzip this one too
You should end up with several file, with one of them called blob
For the next step, you will need to install the Android SDK to get the fastboot utility. If you do not know how to use fastboot, you should take a look at this guide.
Once you have installed fastboot, boot your tablet into fastboot mode (Plugin your tablet on your computer's USB, Hold down Power+VolDown, dont press VolUp when prompted, select the USB icon and press VolUp)
Open a command line terminal and navigate to the folder containing the blob file.
Then type the following command:
fastboot -i 0x0B05 flash system blob
For some reason, the transfer seems to fail from time to time, if so, just try again by going back to previous step.
Once the transfer is done and you get that sweet "SUCCESS" printed on your screen, just type the following command to reboot your tablet:
And there you have ! You are now back to stock ROM with fully working 3G
Click to expand...
Click to collapse
Using
fastboot -i 0x0B05 flash system blob
Click to expand...
Click to collapse
is a tad wrong. It works, but only by accident.
You should be using
fastboot -i 0x0B05 flash staging blob
Click to expand...
Click to collapse
The technical reason for why your command works, is because the nvidia bootloader writes files to the staging area before writing it to the partition you specify.
What essentially happens is:
Blob is written to staging
Blob is copied to system (meaning non-booting system)
On reboot, blob is "extracted" from staging and properly flashed.
Step 3 is what makes it work in the end, but you are causing an extra unneeded write to the flash (step 2 is not really needed) (In this case it works, but it potentially increases the risk of bricking)

thx didn´t know that. So all the howto´s are wrong

benoitvdh said:
Hi, followed the steps but it didnt work for me too
Fastboot copies the file but after when it tries to flash it gives an error
sending 'system' (796581 KB)...
OKAY [129.964s]
writing 'system'...
FAILED (remote: (InvalidState))
finished. total time: 182.134s
The Tab shows
signature mismatch
Can you help me?
Click to expand...
Click to collapse
Your probably running Jellybean, if so this HOWTO does'nt work.

Question: What exactly is supposed to happen? First I tried it and got the fail and did it a second time and it seemingly worked. In my command prompt it ended with
"writing 'system' ... OKAY"
and wasn't doing anything after that in the command prompt and on the tablet there was a full status bar so it looked like whatever it was doing it was finished? So I held the power button and I think it was a boot loop ... it just was the ASUS screen with the spinning circle. So I just did it again, failed the first time did it again and now I am where I left off. I guess I will wait a while and see if it says "SUCCESS" on my tablet? And if not I will put in the reboot command? (I probably should have tried that last time instead of holding the power button I forgot about the last couple lines of the guide )
EDIT: Or is it cuz I am flashing the wrong SKU? I didn't know what one my tablet is supposed to be ... its a cyanogenmod build so I don't think I cant find what the SKU is supposed to be. I went with US SKU because I live in the United States but I don't know if that's what it is
EDIT2: After waiting a while with no "SUCCESS" Windows said that adb.exe crashed or something. So I put in the reboot command but now it seems to be stuck on the ASUS loading screen again.

Blackdrag said:
Question: What exactly is supposed to happen? First I tried it and got the fail and did it a second time and it seemingly worked. In my command prompt it ended with
"writing 'system' ... OKAY"
and wasn't doing anything after that in the command prompt and on the tablet there was a full status bar so it looked like whatever it was doing it was finished? So I held the power button and I think it was a boot loop ... it just was the ASUS screen with the spinning circle. So I just did it again, failed the first time did it again and now I am where I left off. I guess I will wait a while and see if it says "SUCCESS" on my tablet? And if not I will put in the reboot command? (I probably should have tried that last time instead of holding the power button I forgot about the last couple lines of the guide )
EDIT: Or is it cuz I am flashing the wrong SKU? I didn't know what one my tablet is supposed to be ... its a cyanogenmod build so I don't think I cant find what the SKU is supposed to be. I went with US SKU because I live in the United States but I don't know if that's what it is
EDIT2: After waiting a while with no "SUCCESS" Windows said that adb.exe crashed or something. So I put in the reboot command but now it seems to be stuck on the ASUS loading screen again.
Click to expand...
Click to collapse
I have a WW TF300T and had no problem flashing a US version.. so its no SKU problem how long did you wait on the ASUS screen with the spinning circle? It took up to 5 mins for me! just wait a lil bit longer next time.. And there comes no "SUCCESS" on the tablet! only a blue bar that should be full after SUCCESS comes up in your Fastboot-COMMANDLINE.. the reboot with the fastboot reboot command from the first page..just give your tab a bit more time.. its like a babe. handle it with care :silly:

Success!
Hazaa! I can confirm that I managed to flash back to stock by flashing the blob to the staging partition. Like so many other, the first flash failed but the second time worked. I now have working 3G again!

0nyx7 said:
I have a WW TF300T and had no problem flashing a US version.. so its no SKU problem how long did you wait on the ASUS screen with the spinning circle? It took up to 5 mins for me! just wait a lil bit longer next time.. And there comes no "SUCCESS" on the tablet! only a blue bar that should be full after SUCCESS comes up in your Fastboot-COMMANDLINE.. the reboot with the fastboot reboot command from the first page..just give your tab a bit more time.. its like a babe. handle it with care :silly:
Click to expand...
Click to collapse
Thanks for the reply 0nyx7!
I had waited a while, maybe 10-20 minutes? But I don't remember entirely. I tried flashing the stock firmware a few times but eventually I just gave up. I didn't like the possibility that my tablet was bricked so I just aborted mission and decided to go back to cm10 where it was safe. I just looked up a post on how to flash Clockworkmod Recovery with fasboot and then flashed a cm10 nightly I already had on my internal storage. So all is good... Mostly.

Nexus 7 stuck at "Google" screen

Hello Forums,
I went on vacation like 2 months ago, and i brought my Nexus with me, and I thought i had lost it. My relatives found it and it was handed to me. With this being said, my nexus was uncharged for the duration of the time, and when i tried to recharge it, it flickered several times and nothing happened. I found that i should hard reset and and put it into recovery mode, but it would always say booting failed.
I searched everywhere and found that i should try and flash the stock image so i looked up several guides on how to do so. On this site i found to use a Wugfresh toolkit. When i tried flashing on both occasions, each time the cmd prompt would come up it would say
sending 'bootloader' <2096KB>....
FAILED <remote: Bootloader is locked.>
finished. total time: 0.012s
rebooting into bootloader....
OKAY
finished. total time:0.021s
<waiting for device>
BUT, my device won't ever reboot. I would always have to press power vol up and vol down.
I noticed that this is a reacurring pattern. I is unable to reboot on its own.I searched everywhere and cannot find a solution.
I am able to get into the menu
FASBOOT MODE
PRODUCT NAME
VARIANT
ETC ETC
LOCK STATE-LOCKED
I would think to unlock it, but it wont ever reboot when i tried to.
I have also tried opening cover to see if the battery wire was loose, it was slightly out of place but i put it back, but same thing.

Since you can access the bootloader, I would recommend learning how to use fastboot. I had a similar situation, and fastboot saved my N7. I'm not that experienced with fastboot, but learning was pretty simple. Search Google for instructions on how to set up SDK. Let me know if you run into any problems, and I'll do what I can to help.

chrisbo4 said:
Since you can access the bootloader, I would recommend learning how to use fastboot. I had a similar situation, and fastboot saved my N7. I'm not that experienced with fastboot, but learning was pretty simple. Search Google for instructions on how to set up SDK. Let me know if you run into any problems, and I'll do what I can to help.
Click to expand...
Click to collapse
im following a guide, but im stuck where i have to update my drivers. since my Nexus is off, when i go into the device manager, all i see is APX under other devices. Do i turn on my nexus in bootloader, or update the APX drivers?
EDIT: I did get the drivers working when i put it into bootloader , so when i look at the device manager i see "Google Nexus 7 Bootloader Interface". When i put in adb devices in the command prompt, i see
List of devices attached
C:\Users\etc\etc\....
I dont get a serial number, i dont know what im doing wrong ):

Arroma said:
im following a guide, but im stuck where i have to update my drivers. since my Nexus is off, when i go into the device manager, all i see is APX under other devices. Do i turn on my nexus in bootloader, or update the APX drivers?
EDIT: I did get the drivers working when i put it into bootloader , so when i look at the device manager i see "Google Nexus 7 Bootloader Interface". When i put in adb devices in the command prompt, i see
List of devices attached
C:\Users\etc\etc\....
I dont get a serial number, i dont know what im doing wrong ):
Click to expand...
Click to collapse
Okay, and the command prompt is where I had some trouble too. Unfortunately all of the tutorials I read assume that that the user already knows how to use a command prompt, which I didn't. So you'll want to make sure your SDK manager has "platform-tools" & "USB drivers" up to date. Also make sure that your factory image has been extracted and placed in the platform-tools folder. I used 7-zip to extract.
When you're in the command prompt, type "cd android-sdk-windows", then "cd platform-tools". From there you're ready to use fastboot. You can type "fastboot devices", and you should (if everything is installed correctly) see your devices serial number displayed. From there you can type the necessary commands to restore your device.

Arroma said:
Hello Forums,
Click to expand...
Click to collapse
android adb folder (password to zip is jt100)
^ download that and extract the Android folder to the root of your C: harddrive (so it'll be C:/Android) this is the main adb/fastboot/whatever folder you'll ever need, ever.
- hold down shift and then right click within the android folder and select "open a command prompt here" (or something like that)
Arroma said:
i do see the serial, but now im unsure of what commands to use, the guide said to do oem fastboot unlock, but it failed
Click to expand...
Click to collapse
-fyi...the command 'adb devices' is for when your device is booted up to the android homescreen and 'fastboot devices' is obviously when you're in bootloader
-'fastboot oem unlock' is to unlock the bootloader
then, if you have the 4.3 factory image from google on hand...
-extract the initial zip, and you'll get like 5 files
-copy those 5 files to the same C:/Android folder from earlier
-make sure your nexus is in bootloader screen and then just double click the 'flashall' .BAT file (if you're running windows OS) and android will auto wipe and flash everything
-just let it sit and wait for your device to boot to setup screen

chrisbo4 said:
Okay, and the command prompt is where I had some trouble too. Unfortunately all of the tutorials I read assume that that the user already knows how to use a command prompt, which I didn't. So you'll want to make sure your SDK manager has "platform-tools" & "USB drivers" up to date. Also make sure that your factory image has been extracted and placed in the platform-tools folder. I used 7-zip to extract.
When you're in the command prompt, type "cd android-sdk-windows", then "cd platform-tools". From there you're ready to use fastboot. You can type "fastboot devices", and you should (if everything is installed correctly) see your devices serial number displayed. From there you can type the necessary commands to restore your device.
Click to expand...
Click to collapse
i do see the serial, but now im unsure of what commands to use, the guide said to do oem fastboot unlock, but it failed

Arroma said:
i do see the serial, but now im unsure of what commands to use, the guide said to do oem fastboot unlock, but it failed
Click to expand...
Click to collapse
The command you'll want to use if you want your bootloader unlocked is "fastboot oem unlock" Just a hint, every command should begin with "fastboot". If all you want to do is restore the factory image, I can help you with those commands as well.

You're limited to Fastboot commands when your device is booted to the boot loader. ADB commands only work if you can get booted into Android. You'll have to recover your tablet strictly using fastboot commands. Wugfresh's root toolkit should work now that you have the device drivers loaded. First step is to unlock the boot loader. Then proceed with flashing the factory image.

wugfresh doesnt work, it always fails to unlock, even using the commands, says Unknown Error

Arroma said:
wugfresh doesnt work, it always fails to unlock, even using the commands, says Unknown Error
Click to expand...
Click to collapse
read my earlier post, forget using the damn toolkit

@jt.one I agree using a toolkit is a waste of time, especially when the OP has already accessed fastboot. He's practically done.

mandad since
jt.one said:
then, if you have the 4.3 factory image from google on hand...
-extract the initial zip, and you'll get like 5 files
-copy those 5 files to the same C:/Android folder from earlier
-make sure your nexus is in bootloader screen and then just double click the 'flashall' .BAT file (if you're running windows OS) and android will auto wipe and flash everything
-just let it sit and wait for your device to boot to setup screen
Click to expand...
Click to collapse
Right so, i did everything you said, and it was working, until somewhere along the middle it failed cause its still locked, but i cant unlock it cause it always fails to unlock due to an unkown error ):

After sending fastboot devices, and getting a serial number, send fastboot oem unlock. Then flash a factory image. Here's a good tutorial on how to flash Android 4.3..

Arroma said:
Right so, i did everything you said, and it was working, until somewhere along the middle it failed cause its still locked, but i cant unlock it cause it always fails to unlock due to an unkown error ):
Click to expand...
Click to collapse
even though you did 'fastboot oem unlock'..... your bootloader refuses to unlock?
now that is strange...

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"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
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"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
jt.one said:
even though you did 'fastboot oem unlock'..... your bootloader refuses to unlock?
now that is strange...
Click to expand...
Click to collapse
i dont understand either, errors everytime ):

You don't see a fastboot response like this?
Then you'll need to tell us specifically, every error message that pops up.

exglynco said:
You don't see a fastboot response like this?
Then you'll need to tell us specifically, every error message that pops up.
Click to expand...
Click to collapse
i do see that, and i use the power button for yes, here ill copy and paste what i saw on the internet some guy is having the same problem im having, only noone replied to his thread
"My problem is that I cant unlock my bootloader.
This is what I tried:
fastboot oem unlock
This is the result:
(bootloader) erasing userdata...
(bootloader) erasing userdata done
(bootloader) erasing cache...
(bootloader) erasing cache done
(bootloader) unlocking...
FAILED (remote: (Unknown error code))
On my device in fastboot it just adds the text "unlocking now......" and nothing happens. If I try to reboot with i.e fastboot reboot-bootloader the device screen is just black, im not sure its even on."
-cant give credit to the guy cause i cant post links yet,
sorry on not being clear enough, i really appreciate your help

Arroma said:
i do see that, and i use the power button for yes, here ill copy and paste what i saw on the internet some guy is having the same problem im having, only noone replied to his thread
"My problem is that I cant unlock my bootloader.
This is what I tried:
fastboot oem unlock
This is the result:
(bootloader) erasing userdata...
(bootloader) erasing userdata done
(bootloader) erasing cache...
(bootloader) erasing cache done
(bootloader) unlocking...
FAILED (remote: (Unknown error code))
On my device in fastboot it just adds the text "unlocking now......" and nothing happens. If I try to reboot with i.e fastboot reboot-bootloader the device screen is just black, im not sure its even on."
-cant give credit to the guy cause i cant post links yet,
sorry on not being clear enough, i really appreciate your help
Click to expand...
Click to collapse
You're device wouldn't boot prior to unlocking the bootloader, right? I would try flashing the factory images, then unlocking the bootloader... if that;s possible.

chtfte was
chrisbo4 said:
You're device wouldn't boot prior to unlocking the bootloader, right? I would try flashing the factory images, then unlocking the bootloader... if that;s possible.
Click to expand...
Click to collapse
im not sure i understand, i cant flash anything because its still locked

Arroma said:
im not sure i understand, i cant flash anything because its still locked
Click to expand...
Click to collapse
I apologize, just a crazy idea I had.

Stock Nexus 7 (Wifi, 2012) Boot Loop and Soft Brick

Hey All,
So here's the deal, I have a nexus 7 Wifi 2012, and it's soft bricked into a boot loop. Some FAQS:
1) It boot loops forever.
2) Yes, I can get into fast boot.
3) The recovery image is currently destroyed, so even though I have the recovery option, it just boots to a 'Dead Android' Image.
4) Fastboot is currently locked.
5) USB Debugging mode was of off and because of the boot loop, I can't turn it on.
6) I've tried with ADB Fastboor, and with WugFreshs Nexus Root Tool (v2.1.0) to restore the recovery image, or the system itself, and I'm having no luck.
7) I've referred to threads such as this one: http://forum.xda-developers.com/showthread.php?t=2595736, and I still can't find a solution.
While I've tried many things, if I can solve getting the bootloader to unlock, then I'll be on my merry way. When I use the Nexus root toolkit, I follow the instructions to unlock the bootloader, I get the splash screen asking me if I want to unlock it, I select 'Yes', and then the device just powers off. It doesn't restart (Even though that's what it says it will do). If I turn it on at the power switch, I get 4 swirling dots (Which is different from the boot loop I get stuck on usually), and my PC tries to install a device driver called 'MTP USB Device', but it fails.
I've tried installing the Google drivers as per: http://developer.android.com/sdk/win-usb.html and here: http://developer.android.com/tools/extras/oem-usb.html and I'm confident I've done it right, but no dice. I suspect it's a drivers issue, but I'm getting really stuck on solving this.
Just as a note, when using ADB Fastboot, I get an unknown failed error:
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
Can anyone assist?

If you can get into fastboot mode, have you tried flashing a custom recovery or are you unable to do that also?

TheGoldenMagikhrp said:
If you can get into fastboot mode, have you tried flashing a custom recovery or are you unable to do that also?
Click to expand...
Click to collapse
Hey,
Thanks for the response. I wasn't having much luck with a custom recovery, but my understanding was that I wouldn't be able to flash a custom recovery without unlocking the bootloader?
If you can recommend a recovery image for this device, I'd be more then willing to give it a second shot.

HDCerberus said:
Hey,
Thanks for the response. I wasn't having much luck with a custom recovery, but my understanding was that I wouldn't be able to flash a custom recovery without unlocking the boot-loader?
If you can recommend a recovery image for this device, I'd be more then willing to give it a second shot.
Click to expand...
Click to collapse
I would personally recommend the latest built of the TWRP recovery, that one seemed to work for me when I was stuck in a similar situation. Unless I'm mistaken, I have flashed recovery with a locked boot-loader before on the same device. If the recovery doesn't work, try downloading the 'Nexus Root Toolkit' (this should work assuming that your computer can recognize the Nexus in some way). What I'm primarily trying to achieve here is a custom recovery as it would be a good starting point for solving this boot-loop problem!

TheGoldenMagikhrp said:
I would personally recommend the latest built of the TWRP recovery, that one seemed to work for me when I was stuck in a similar situation. If the recovery doesn't work, try downloading the 'Nexus Root Toolkit' (this should work assuming that your computer can recognize the Nexus in some way). What I'm primarily trying to achieve here is a custom recovery as it would be a good starting point for solving this boot-loop problem!
Click to expand...
Click to collapse
Thanks, I'll try this when I get home and update. I've been using the 'Nexus Root Toolkit' and I'm getting a response from it, but was struggling after that. Will update with how it goes.

TheGoldenMagikhrp said:
I would personally recommend the latest built of the TWRP recovery, that one seemed to work for me when I was stuck in a similar situation. Unless I'm mistaken, I have flashed recovery with a locked boot-loader before on the same device. If the recovery doesn't work, try downloading the 'Nexus Root Toolkit' (this should work assuming that your computer can recognize the Nexus in some way). What I'm primarily trying to achieve here is a custom recovery as it would be a good starting point for solving this boot-loop problem!
Click to expand...
Click to collapse
Seems I've had no luck. The Device responds, but just times out when it tries to apply the recovery image. Here's the log from Nexus Root:
Nexus Root Toolkit v2.1.0
Masterlists:
- LatestToolkitFiles.ini 3105
- AndroidDeviceListFull.ini 3105
- AndroidDeviceListFlash.ini 3105
NAKASI-GROUPER: Android 4.1.0 - Build: JRN84D
Live log initiated [2015-12-18]:
Checking ADB/FASTBOOT Connectivity
adb devices
fastboot devices
015d3b65f653ec0a fastboot
Connectivity Status: Fastboot Device Connected
Temporarily Booting modified boot.img to enable running privileged commands...
fastboot boot "I:\Program Files (x86)\WugFresh Development\Nexus Root Toolkit\data\Modified_Boot\modified_boot_nakasi_4.1.0_JRN84D.img"
Waiting for your device...
Any ideas what to try next?

HDCerberus said:
Seems I've had no luck. The Device responds, but just times out when it tries to apply the recovery image. Here's the log from Nexus Root:
Nexus Root Toolkit v2.1.0
Masterlists:
- LatestToolkitFiles.ini3105
- AndroidDeviceListFull.ini3105
- AndroidDeviceListFlash.ini3105
NAKASI-GROUPER: Android 4.1.0 - Build: JRN84D
Live log initiated [2015-12-18]:
Checking ADB/FASTBOOT Connectivity
adb devices
fastboot devices
015d3b65f653ec0afastboot
Connectivity Status: Fastboot Device Connected
Temporarily Booting modified boot.img to enable running privileged commands...
fastboot boot "I:\Program Files (x86)\WugFresh Development\Nexus Root Toolkit\data\Modified_Boot\modified_boot_nakasi_4.1.0_JRN84D.img"
Waiting for your device...
Any ideas what to try next?
Click to expand...
Click to collapse
Does the same thing happen when to attempt to unlock the boot-loader?
Edit: Try using an alternate method to the tooklit, use the Windows drivers and open the command window in 'platform-tools' then use the 'fastboot oem unlock' command.
Edit 2: Can you also try flashing either a full stock ROM from Google or a Cyanogen Mod ROM via fastboot (using the command prompt method).

TheGoldenMagikhrp said:
Does the same thing happen when to attempt to unlock the boot-loader?
Edit: Try using an alternate method to the tooklit, use the Windows drivers and open the command window in 'platform-tools' then use the 'fastboot oem unlock' command.
Edit 2: Can you also try flashing either a full stock ROM from Google or a Cyanogen Mod ROM via fastboot (using the command prompt method).
Click to expand...
Click to collapse
Thanks for the help so far. I've tried all of these a few times, and the issue I have is I can't get the bootloader to unlock. If I try flashing the recovery, I get FAILED (remote: Bootloader is locked.) in the command line.
When I try 'fastboot oem unlock', this fails for some unknown reason, with the following in the command line:
(bootloader) erasing userdata...
(bootloader) erasing userdata done
(bootloader) erasing cache...
(bootloader) erasing cache done
(bootloader) unlocking...
FAILED (remote: (Unknown error code))
finished. total time: 6.870s
And while the device does ask me if I want to unlock the bootloader, it freezes with an 'Unlocking now...' message in the top left, while it doesn't appear to actually unlock the device.
Is my device beyond repair, or is there anything else I can try?

HDCerberus said:
Thanks for the help so far. I've tried all of these a few times, and the issue I have is I can't get the bootloader to unlock. If I try flashing the recovery, I get FAILED (remote: Bootloader is locked.) in the command line.
When I try 'fastboot oem unlock', this fails for some unknown reason, with the following in the command line:
(bootloader) erasing userdata...
(bootloader) erasing userdata done
(bootloader) erasing cache...
(bootloader) erasing cache done
(bootloader) unlocking...
FAILED (remote: (Unknown error code))
finished. total time: 6.870s
And while the device does ask me if I want to unlock the bootloader, it freezes with an 'Unlocking now...' message in the top left, while it doesn't appear to actually unlock the device.
Is my device beyond repair, or is there anything else I can try?
Click to expand...
Click to collapse
Well there's one final solution I can think of, keep in mind, there are many people on this forum and surely many others with the same problem, so there might be someone with a solution out there. But here's what I'm thinking. Download an extracted bootloader.img file and flash it to the Nexus 7. You see I would have suggested this earlier but the reason I didn't is because of the risks that come along with it, I wanted to try all the safe, reasonable options to see if they worked but clearly not. I would personally take extreme caution while doing this and only use it as a last resort. I'm so hesitant in recommending this solution as it can cause what is known as a hard bricked device (I'm sure you're aware what this is already) but basically it means your device could potentially never boot again.
If you want further help, let me know and I'll help but keep in mind that if you choose to do this, you're doing so at your own risk!

TheGoldenMagikhrp said:
Well there's one final solution I can think of, keep in mind, there are many people on this forum and surely many others with the same problem, so there might be someone with a solution out there. But here's what I'm thinking. Download an extracted bootloader.img file and flash it to the Nexus 7. You see I would have suggested this earlier but the reason I didn't is because of the risks that come along with it, I wanted to try all the safe, reasonable options to see if they worked but clearly not. I would personally take extreme caution while doing this and only use it as a last resort. I'm so hesitant in recommending this solution as it can cause what is known as a hard bricked device (I'm sure you're aware what this is already) but basically it means your device could potentially never boot again.
If you want further help, let me know and I'll help but keep in mind that if you choose to do this, you're doing so at your own risk!
Click to expand...
Click to collapse
Hey,
I appreciate the help so far, but I actually already tried this a while back, and the error I get then is:
sending 'bootloader' (2100 KB)...
FAILED (remote: Bootloader is locked.)
finished. total time: 0.020s
So it looks like I can't unlock the bootloader as it's bust, and I therefore can't replace it with a working bootloader, and thus I'm stuck.....

HDCerberus said:
Hey,
I appreciate the help so far, but I actually already tried this a while back, and the error I get then is:
sending 'bootloader' (2100 KB)...
FAILED (remote: Bootloader is locked.)
finished. total time: 0.020s
So it looks like I can't unlock the bootloader as it's bust, and I therefore can't replace it with a working bootloader, and thus I'm stuck.....
Click to expand...
Click to collapse
Hmmm, this is quiet a tricky situation, I was sure that I was able to flash a bootloader even with the current bootloader locked previously. I've completely run out of advice or solutions for the problem, the only other think I can think of doing is attempting to simulate the problem and have a play around with it myself, otherwise, I would suggest consulting Asus or Google with your issue. I'll let you know if I find another potential solution but in the meantime I would recommend either having a look around on the internet some more or looking to have it fixed by Google or Asus if you think it's worth it.

TheGoldenMagikhrp said:
Hmmm, this is quiet a tricky situation, I was sure that I was able to flash a bootloader even with the current bootloader locked previously. I've completely run out of advice or solutions for the problem, the only other think I can think of doing is attempting to simulate the problem and have a play around with it myself, otherwise, I would suggest consulting Asus or Google with your issue. I'll let you know if I find another potential solution but in the meantime I would recommend either having a look around on the internet some more or looking to have it fixed by Google or Asus if you think it's worth it.
Click to expand...
Click to collapse
Cheers, but I think I've hit the end of the road here. Into the trash it goes!

HDCerberus said:
Cheers, but I think I've hit the end of the road here. Into the trash it goes!
Click to expand...
Click to collapse
If that's what you think is necessary. Sorry I couldn't help.
Sent from my Xperia Z Ultra using Tapatalk

SOLVED: ZenFone 3 Laser (ZC551KL) dm-verity no boot

I set my phone down last night and came back to it with this screen and it will not boot into Android. It's not rooted or unlocked, the only thing I can think of is that an OTA killed it somehow, although I wasn't alerted to one or initiate anything.
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
When I touch any of the buttons this screen comes up. Rebooting just starts the process over again.
I can see the phone with fastboot, and I tried flashing the factory boot.img again with no luck. I'm unable to find the factory recovery.img or system.img anywhere to give that a shot.

that was happened to my zenfone 3 5.5 too,
solution just flash firmware from asus with stock recovery

I can't get into the recovery to flash, unless I'm doing something wrong, I can only get to the bootloader and I cant find the proper .img files to flash with fastboot.

when I select reboot to recovery in fastboot it just reboots to the dm-verity screen again. It's like the recovery is just gone.

Just got off the phone with Asus, they were no help at all. I asked for the recovery image and they don't have one, what?
Does anyone know of a way to extract data from the internal storage in fastboot? I'd like to get a copy of that before I send it in...

SOLVED!
I created a modified UPDATE.ZIP using this method and flashed in fastboot like so:
Code:
fastboot flash system update.zip
That allowed the phone to boot to recovery, from there I flashed the firmware that is available to download from the Asus website in recovery and the phone booted up with no loss of data

So I did this with the newest firmware.
I can boot to recovery now (couldn't before just like yourself) but on the flash from fastboot I got
>target reported max download size of 536870912 bytes
Invalid sparse file format at header magi
error: write_sparse_skip_chunk: don't care size 2008017072 is not a multiple of
the block size 4096
erasing 'system'...
OKAY [ 0.010s]
sending sparse 'system' (0 KB)...
error: write_sparse_skip_chunk: don't care size 2008017072 is not a multiple of
the block size 4096
error: write_sparse_skip_chunk: don't care size 2008017072 is not a multiple of
the block size 4096
OKAY [ 0.030s]
writing 'system'...
FAILED (remote: buffer overreads occured due to invalid sparse header)
finished. total time: 0.060s
Meaning something failed.
I'm stuck on the ASUS boot screen
Tried a Factory Reset from recovery, still nothing.
I tried fastboot erase system -w
then reflashing the newest firmware, and still nothing
Since I can get to the recovery now, does anyone have a stock .img i can flash? or any other ideas?

Try flashing the firmware .zip from either the SD card or sideload in recovery.

Niemer said:
Try flashing the firmware .zip from either the SD card or sideload in recovery.
Click to expand...
Click to collapse
I will try that tonight. Thanks!

unknown partition 'wallox.zip
SOLVED
Hi, Your response has been very useful, but I still Have a Problem With regard. The Times tells me That does not FIND the zip file needed, other times: Unknown Partition 'wallox.zip
What's the Problem?
ps. Excuse my language

Niemer said:
SOLVED!
I created a modified UPDATE.ZIP using http://forum.xda-developers.com/showpost.php?p=69380242&postcount=3 method and flashed in fastboot like so:
Code:
fastboot flash system update.zip
That allowed the phone to boot to recovery, from there I flashed the firmware that is available to download from the Asus website in recovery and the phone booted up with no loss of data
Click to expand...
Click to collapse
the link is broken... can you please give the update.zip file. Thanks
[EDIT: update.zip found ! phone recovered... all ok, thanks ]

Niemer said:
SOLVED!
I created a modified UPDATE.ZIP using http://forum.xda-developers.com/showpost.php?p=69380242&postcount=3 method and flashed in fastboot like so:
Code:
fastboot flash system update.zip
That allowed the phone to boot to recovery, from there I flashed the firmware that is available to download from the Asus website in recovery and the phone booted up with no loss of data
Click to expand...
Click to collapse
link not works

help
hello to all guys, can someone give me the modified file fastboot flash system update.zip .. I'd be very grateful ..
Hello

edowar said:
that was happened to my zenfone 3 5.5 too,
solution just flash firmware from asus with stock recovery
Click to expand...
Click to collapse
how did you able to flash sir? Mine is coming on same dm-verity screen again and again.

akashnigam said:
how did you able to flash sir? Mine is coming on same dm-verity screen again and again.
Click to expand...
Click to collapse
Create the modified update as instructed here https://forum.xda-developers.com/showpost.php?p=69380242&postcount=3
I can boot into the setup dialogue now but the phone keeps shutting down on its own after a few seconds. Anyone experiencing the same thing?

Hi. I just made a post with a fairly comprehensive solution to the brick-problem that I had. If your problem is anything like mine was, then it should be useful.
https://forum.xda-developers.com/zenfone-3/help/unbricking-zenfone-3-ze552kl-dm-verity-t3563970
Much thanks to Niemer for being the inspiration for the solution. And thanks to everyone in the forum for asking good questions and posting good responses.

Niemer can you be so kind and upload your update.zip anywhere?

Lets open this tiny beast up!!!!

One click solution to unbrick and fix "no recovery mode" on zenfone 3 laser (zc551kl)
Just accidentally i found a "one click" solution to unbrick / fix loop boot / fix no recovery mode... My story started after i unlocked my Zenfone 3 Laser ZC551KL (Z01BDC) bootloader with the official tool from Asus. After i couldn't find any custom rom for this phone, i wanted to re-lock my bootloader to receive FOTA updates, so, i flashed boot.img and recovery.img from a Zenfone 2 Laser as i couldn't find files for mine, and i soft bricked it... boot loop, would only boot in bootloader, can't even access the "recovery" to apply the firmware update from sd card. After couple days of searching EVERY SINGLE WEB SITE for a viable, easy solution to fix my phone, and hundreds of files, firmwares, tools downloaded, i found it, right under my nose... Earlier in the process of looking for a solution, i downloaded a stock firmware zip (Asus_ZenFone_3_Laser_ZC551KL_WW-ZC551KL_13.40.104.1_20161014, who also included SP_Flash_Tool_v5.1720_Win. It's roughly 1.84 Gb, and 4.07 Gb after unzipping. So just download the zip, unzipp it and go into the folder and look for subfolder "Firmware+ Tool", where you'll find lots of files... look for "flashall_AFT", it's a "Windows Command script" file... double click it with your phone connected in fastboot mode, and wait. Will take 5-10 minutes, just be patient. I lost all my hopes while i was trying this just for sick of it, i left it "work" and went for a smoke... When i came back, my phone was on, with the Android Welcome setting screen.... I think i cried of happiness in my brain. Hope will help others fix the issue. Just to note, this method did not relocked my bootloader, is still unlocked, but what the hell, my phone is alive again. Aaaa, and even if i had Android 7.1.1 before, after this fix, i have Android 6.1 which i will keep till August 2018 when we'll get the Oreo for Zenfone 3 Laser. If you want to, after this fix, you can go to Asus page and download the latest version you'll like and install it manually. Here is the only link where you need to go and download the zip file to fix (it will redirect you to Mediafire for download): http://stockandroidrom.com/asus-zenfone-3-laser-zc551kl-usb-driver/
Wish you all the best.

Need Latest Firmware+Tool for my Asus zc551kl please. Update.zip and Rother method not working. Progress bar on bootscreen 2 sec delay and power off. I'm no update later 6.0.1 with unlocking bootlooader. Please,help me

Installing lineage OS - stuck on start screen, would very much appreciate assistance

I've been following this guide with the aim of installing lineageos on a 6T I just bought: https://lineageosroms.com/fajita/#installation.
I downloaded the following files in advance:
copy-partitions-20200903_1329.zip
lineage-18.1-20211230-nightly-fajita-signed.zip
lineage-18.1-20211230-recovery-fajita.img
I have followed all the steps up to and including steps 6 of part 'Temporarily booting a custom recovery using fastboot'. The last part that appeared to run successfully was step 5 e.g.: fastboot flash boot lineage-18.1-20211230-recovery-fajita.img
Here is the output of the commands run on the host (serial number redacted):
adb reboot bootloader
➜ fastboot devices
******* fastboot
➜ fastboot oem unlock
OKAY [ 0.036s]
Finished. Total time: 0.036s
➜ adb reboot bootloader
➜ fastboot devices
******** fastboot
➜ fastboot flash lineage-18.1-20211230-recovery-fajita.img
unknown partition 'lineage-18.1-20211230-recovery-fajita.img'
fastboot: error: cannot determine image filename for 'lineage-18.1-20211230-recovery-fajita.img'
➜ fastboot flash boot lineage-18.1-20211230-recovery-fajita.img
Sending 'boot_a' (65536 KB) OKAY [ 1.543s]
Writing 'boot_a' OKAY [ 0.332s]
Finished. Total time: 1.973s
➜ fastboot devices
******** fastboot. ### This is where I just see the message about the OEM being unlocked and integrity.
➜ adb sideload copy-partitions-20200903_1329.zip ## I ran this even though I just saw the integrity message in the hope it would then enable me to select 'Apply Update'.
adb: sideload connection failed: no devices/emulators found
adb: trying pre-KitKat sideload method...
adb: pre-KitKat sideload connection failed: no devices/emulators found
➜ fastboot devices
******** fastboot
NB I once accidentally wrote fastboot flash lineage-18.1-20211230-recovery-fajita.img instead of fastboot flash boot lineage-18.1-20211230-recovery-fajita.img (i.e. I missed off the 'boot'). However, as I got the immediate error "fastboot: error: cannot determine image filename for 'lineage-18.1-20211230-recovery-fajita.img'" I suppose it was a no-op and hopefully didn't do any harm.
The problem is that when I then booted into the phone with volume down and power (step 6) I just got a screen with a message about the OEM being unlocked and phone integrity.
I powered the phone off after waiting a while with volume up and power. Then powered on. Same message. Since then I've tried powering off and on with both volume up and volume down and power. I get into a mode where I can select start, restart boot loader, recovery mode and power off.
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
As I understood I'm trying to get into 'recovery mode' I selected that, but that just restarts the phone. I think that just took me back to the integrity message and at that point I ran the command adb sideload copy-partitions-20200903_1329.zip in the hope it would bring up the option to apply the update. However, now whenever I restart the phone I don't see the integrity message, just the 'options' menu (please see 'start' option above). I don't see the OEM unlocked/integrity message any more regardless of how I start the phone.
I have now tried basically all the options including restart the bootloader. All lead back to the same screen. When I have the phone connected to my mac via usb, I can still at least see it with fastboot devices:
fastboot devices
******** fastboot
As the guide I'm following doesn't show what you ought to see at each step I'm not sure what should have happened on step 6 when booting into recovery mode (this is my first flash) but as the guide says
'On the device, select “Apply Update”, then “Apply from ADB” to begin sideload.' I'm guessing it should at least have booted into a UI different to the one I'm seeing.
Is there anything I can do now? Should I try flashing another recovery image? Re running anything? Is it 'bricked'?
Really appreciate any guidance.

PS one thing I've noticed is that the instructions of 6T (https://lineageosroms.com/fajita/#installation) say we should run
fastboot flash boot <recovery_filename>.img
whereas the instructions for earlier and later models of the one plus (and other brands) say to run
fastboot flash recovery <recovery_filename>.img
Of course this might be correct, but does anyone know if this is a mistake in the instructions - i.e. should it have been 'recovery' not 'boot' for the 6/6T?
---- EDIT -----
Having looked up some documentation on fastboot (which say the structure of the command is basically fastboot flash <partition> <filename>) and then read around a bit on partitions on Android phones, I'm getting the impression android phones pretty much always have a recovery partition, which would make me think that the 'boot' command is indeed wrong. That said, I've got next to no experience with this so it's hard to be sure that the command isn't correct for some reason I'm not aware of, that only pertains to a few generations of phones.
Anyone?
--- EDIT 2 ----
The maintainers of the wiki.lineageos.org have confirmed to me that the line fastboot flash boot <recovery_filename>.img is written as intended. So still at square one.
Any ideas, anyone?

FWIW I got there. In case it helps anyone to know any of the sordid details, first I flashed back the stock ROM using this thread. Worked pretty much as described albeit I had to unzip the images folder and move the bat file into it so it found the images (first had to get hold of a windows machine).
Once I had it installed again I took an android update on the device. I think it highly likely that this was the cause of the original issue reported above - following the lineageOS wiki would probably have worked from that point, but I never found out as I decided I wanted TWRP anyway and used that as my custom recovery instead. That said, I now realise I could just as well have only installed TWRP after flashing lineage, as flashing LineageOS wiped TWRP.
BTW, I really can't fathom why I either didn't clock or ignored the message about making sure you're on the latest 11 firmware (in a red box!) at the top of the lineageOS install wiki. I don't remember seeing it but perhaps I just thought it would be fine as it was a 'fresh' phone (that had probably lying in a box for a year or so). Anyway, lesson learned.
Had to scramble over some other issues, involving booting a temp 'test' TWRP from crdroid first before flashing the official one, described around this page. I also had an odd 'no system' message in TWRP after wiping the existing system (following these instructions to check which bits to wipe when using TWRP before flashing a custom ROM). Anyone reading might want to check those instructions by asking on a lineageos forum if it makes sense to wipe 'system' on TWRP before flashing the lineage ROM - as I got a message after flashing lineage (in TWRP, before rebooting) that there was no 'system'. However it rebooted (with an error re corrupt user data that I was able to fix just by allowing lineage to wipe the user data again), so it's hard to see how that report of there being no system can have been strictly accurate.
But. I. got. there.

PS now I remember why I didn't see the warning to update the firmware. I was (unknowingly) viewing a repost (on lineageosroms) rather than the original wiki (on wiki.lineageos.org). Beware

i have the same thing but on a newer phone, my pc cant see it so im stuck here for now