Develop Bugs

Can't find valid operating system - Bootloader locked

Have been using my pixel 3xl stock; no roms or anything and I was just checking my phone and I saw can't find valid operating system. I've tried to flash the latest image to it but can't because the bootloader is locked. I've tried to unlock the bootloader but can't and adb doesn't detect a device so I can't seem to sideload it either. Any ideas? Any help is much appreciated as it seems that I can't request a repair through Google's site either.
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flashing unlock
FAILED (remote: 'flashing unlock is not allowed')
Finished. Total time: 0.358s
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flashing unlock_critical
FAILED (remote: 'Invalid argument unlock_critical')
Finished. Total time: 0.052s
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot oem unlock
FAILED (remote: 'Invalid oem command unlock')
Finished. Total time: 0.052s
C:\Program Files (x86)\Android\android-sdk\platform-tools>adb devices
List of devices attached
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot devices
89SY0AW5W fastboot
Fastboot mode
Product Revision: crosshatch MP1.0(ROW)
Bootloader version: b1c1-0.1-5004167
Secure boot: Production
NOS production: yes
DRAM:4GB Micron LPDDR4x
UFS: 64GB Micron
Device state: locked
Enter reason: reboot bootloader

mikegreenberg4515 said:
Have been using my pixel 3xl stock; no roms or anything and I was just checking my phone and I saw can't find valid operating system. I've tried to flash the latest image to it but can't because the bootloader is locked. I've tried to unlock the bootloader but can't and adb doesn't detect a device so I can't seem to sideload it either. Any ideas? Any help is much appreciated as it seems that I can't request a repair through Google's site either.
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flashing unlock
FAILED (remote: 'flashing unlock is not allowed')
Finished. Total time: 0.358s
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flashing unlock_critical
FAILED (remote: 'Invalid argument unlock_critical')
Finished. Total time: 0.052s
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot oem unlock
FAILED (remote: 'Invalid oem command unlock')
Finished. Total time: 0.052s
C:\Program Files (x86)\Android\android-sdk\platform-tools>adb devices
List of devices attached
C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot devices
89SY0AW5W fastboot
Fastboot mode
Product Revision: crosshatch MP1.0(ROW)
Bootloader version: b1c1-0.1-5004167
Secure boot: Production
NOS production: yes
DRAM:4GB Micron LPDDR4x
UFS: 64GB Micron
Device state: locked
Enter reason: reboot bootloader
Click to expand...
Click to collapse
Just curious: Google or Verizon Pixel 3 XL?
If Verizon you will not be able to unlock the bootoader.
Have you downloaded the latest SDK Platform-tools r28.0.1?
It is detecting your device:
"C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot devices
89SY0AW5W fastboot"
Did you try going to Settings > System > Advanced > System Update?
If that doesn't help, go here, Factory Images for Nexus and Pixel Devices and read the flashing instructions.
If it is a Google Pixel 3 XL: [Guide] Pixel 3 XL Android 9.0 (Pie) Unlock/Root/Install Images/Kernels/Recovery + December 2018 Security Patch

try sideloading the full OTA.

uicnren said:
try sideloading the full OTA.
Click to expand...
Click to collapse
Can't sideload twrp-3.2.3-2 adb not working.

Homeboy76 said:
Can't sideload twrp-3.2.3-2 adb not working.
Click to expand...
Click to collapse
You'd sideload the ota with the stock recovery. This is what I'd recommend doing too if the bootloader is locked.
Further to the OP, adb works in recovery not the bootloader so your device probably will be detected by adb and you should be able to sideload the ota.
Sent from my [device_name] using XDA-Developers Legacy app

Are you able to get into Recovery (not bootloader) and do a factory reset?

The whole OP sounds weird. He wasn't doing anything to modify the system and all of a sudden there is no system? He can't ask Google for support? Further explanation is needed before any suggestions would make sense. If the phone is defective then it needs to be returned no matter where it was purchased or not.

jd1639 said:
You'd sideload the ota with the stock recovery. This is what I'd recommend doing too if the bootloader is locked.
Further to the OP, adb works in recovery not the bootloader so your device probably will be detected by adb and you should be able to sideload the ota.
Click to expand...
Click to collapse
You're right, I forgot about this: Full OTA Images for Nexus and Pixel Devices - Updating instructions

Recently purchased two Pixel 3 XL's . Wife came home from the mall and handed me her stock phone with the same message. Couldn't find a valid operating system. I wasn't able to sideload a stock rom. The device was factory locked and I didn't enable developer options on her phone.
I called Google and they quickly issued an RMA. The replacement will be delivered tomorrow and expedited next day delivery.
My phone on the other hand has TWRP,Magisk with stock ROM. I suppose I'll have to unlock and set hers up .
Arc

My Verizon Google Pixel 3xl does the exact same thing...
I too have the same thing in my phone can I purchase from Verizon 2 months ago says product revision crosshatch mp1. 0 in parentheses row says a bootloader version is b-1 C1 same serial number secure boot says production nice production yes dram 4GB micron LPD are forex and device State locked enter reason combo key. I did not mess with this phone nor have I put on developer I don't even know what developer options are my question is this why is Verizon acting like they don't know what the heck I'm talking about. Can someone do this remotely to my phone. Is it bad, you know for the person who doesn't know about computers

uicnren said:
try sideloading the full OTA.
Click to expand...
Click to collapse
no recovery mode.
recovery mode print "no commad" and a android robot

manyer said:
no recovery mode.
recovery mode print "no commad" and a android robot
Click to expand...
Click to collapse
That's actually ok. When you're on that screen, press and hold POWER then press and release VOLUME UP, then release POWER.
"find somebody that you think is undeserving of your compassion and give it to them" - Christian Picciolini

Similar problem
I have a similar problem,
I had rooted the device with Magisk and everything was work fine. Then I wanted to try locking the bootload to see if it can be done.
I ran 'fastboot flashing lock' and clicked the power button to wipe user data.
After the above device shows "Can't find valid operating system. The device will not start". I rebooted in bootloader mode and tried unlocking and I get the following error.
FAILED (remote: 'flashing unlock is not allowed')
fastboot: error: Command failed

Etrash said:
I have a similar problem,
I had rooted the device with Magisk and everything was work fine. Then I wanted to try locking the bootload to see if it can be done.
I ran 'fastboot flashing lock' and clicked the power button to wipe user data.
After the above device shows "Can't find valid operating system. The device will not start". I rebooted in bootloader mode and tried unlocking and I get the following error.
FAILED (remote: 'flashing unlock is not allowed')
fastboot: error: Command failed
Click to expand...
Click to collapse
Assuming you tried to relock a rooted phone without returning it to completely stock (unrooted, no kernel, pretty much flash-all to both slots), you likely bricked your phone.

sliding_billy said:
Assuming you tried to relock a rooted phone without returning it to completely stock (unrooted, no kernel, pretty much flash-all to both slots), you likely bricked your phone.
Click to expand...
Click to collapse
:crying: Yes I didn't return to stock state before locking... So there is no way to recover at all ?

Etrash said:
:crying: Yes I didn't return to stock state before locking... So there is no way to recover at all ?
Click to expand...
Click to collapse
What does the BL say the device status is? If it says locked, try using recovery to sideload an OTA or factory reset. If by some chance it still says unlocked, try a flash-all of the factory image.

sliding_billy said:
What does the BL say the device status is? If it says locked, try using recovery to sideload an OTA or factory reset. If by some chance it still says unlocked, try a flash-all of the factory image.
Click to expand...
Click to collapse
Recovery and rescue mode both show "can't find valid operating system". Couldn't reboot the device in Recovery and run OTA command.
"https ibb.co/P6wkqyc "
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Etrash said:
Recovery and rescue mode both show "can't find valid operating system". Couldn't reboot the device in Recovery and run OTA command.
"https ibb.co/P6wkqyc "
Click to expand...
Click to collapse
Just looked at your "locked" pic and post. You are hard bricked. Sorry, but a call to Google is really the only advice I have left. Since it was an unlockable device, I assume you got it direct. Hopefully, they can help.

Arcdevilz said:
Recently purchased two Pixel 3 XL's . Wife came home from the mall and handed me her stock phone with the same message. Couldn't find a valid operating system. I wasn't able to sideload a stock rom. The device was factory locked and I didn't enable developer options on her phone.
I called Google and they quickly issued an RMA. The replacement will be delivered tomorrow and expedited next day delivery.
My phone on the other hand has TWRP,Magisk with stock ROM. I suppose I'll have to unlock and set hers up .
Arc
Click to expand...
Click to collapse
They sound like they've been erased over the air. If you bought them second hand im 90% sure they have been erased.

can't unlock bootloader by miflash

i was android 10 custom rom .
i used twrp to wip data .
i used mi flash to flash official android 9 rom to downgrade android 10.
but bymistake i checked flash_all_lock.bat
now the problem is
bootloader is locked + phone start when i choose language and select connection wifi or sim it reboot again
so i'm stuck now ,, no twrp or recovery work ,,
when try flash twrp from fastboot it say FAILED (remote: 'oem unlock is not allowed')
i don't have mi account and i never made one ............
there are the log from mi flash
[5:29:40 AM 2349f23c0005]:info:$fastboot -s 2349f23c0005 flash userdata C:\Users\gowan\OneDrive\Desktop\daisy_global_images_V9.6.11.0.ODLMIFF_8.1\\images\userdata.img ||
[5:29:45 AM 2349f23c0005]:err:Sending 'userdata' (181024 KB) OKAY [ 4.049s]
[5:29:45 AM 2349f23c0005]:err:Writing 'userdata' OKAY [ 1.264s]
[5:29:45 AM 2349f23c0005]:err:Finished. Total time: 5.813s
[5:29:45 AM 2349f23c0005]:info:$fastboot -s 2349f23c0005 set_active a
[5:29:45 AM 2349f23c0005]:err:Setting current slot to 'a' OKAY [ 0.020s]
[5:29:45 AM 2349f23c0005]:err:Finished. Total time: 0.023s
[5:29:45 AM 2349f23c0005]:info:$fastboot -s 2349f23c0005 oem lock 2>&1 | findstr /r "locked!" 2>&1 && fastboot -s 2349f23c0005 reboot
[5:29:46 AM 2349f23c0005]:flash done
[5:29:46 AM 2349f23c0005]rocess exit.
[5:29:46 AM 2349f23c0005]:flashSuccess True
[5:29:46 AM 2349f23c0005]:isFactory False CheckCPUID False
[5:29:46 AM 2349f23c0005]:before:flashSuccess is True set IsUpdate:True set IsDone True
[5:29:46 AM 2349f23c0005]:after:flashSuccess is True set IsUpdate:false set IsDone true
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after this by 3 sec it reboot again

any way or go to shops ?

Are you able to enter in fastboot with keys combo?
If so you might try the following tool
Read carefully the file readme.md before starting
https://github.com/Szaki/XiaomiADBFastbootTools

You can boot twrp in fastboot mode and make a format data ( fastboot boot twrpname.img), use official twrp, try to Finish setup, enable developers options, enable usb debugging oem unlocking options, then go back to fastboot mode and type fastboot oem unlock

Os_Herdz said:
You can boot twrp in fastboot mode and make a format data ( fastboot boot twrpname.img), use official twrp, try to Finish setup, enable developers options, enable usb debugging oem unlocking options, then go back to fastboot mode and type fastboot oem unlock
Click to expand...
Click to collapse
I CAN go to fastboot but same error when flash any thing twrp
twrp is broken no recovery

srepole said:
Are you able to enter in fastboot with keys combo?
If so you might try the following tool
Read carefully the file readme.md before starting
https://github.com/Szaki/XiaomiADBFastbootTools
Click to expand...
Click to collapse
FAILED (remote: 'oem unlock is not allowed')
fastboot: error: Command failed

Maybe this helps
https://androidfilehost.com/?a=show&w=files&flid=38683
Download this Tool and Install, connect your Phone, then use on the right Side Flash factory, choose your original image and install.
Then finish the Phone Setup, activate Developer Options, activate OEM unlock and USB Debugging and retry to unlock and install twrp.

Big-Schrotty said:
Maybe this helps
https://androidfilehost.com/?a=show&w=files&flid=38683
Download this Tool and Install, connect your Phone, then use on the right Side Flash factory, choose your original image and install.
Then finish the Phone Setup, activate Developer Options, activate OEM unlock and USB Debugging and retry to unlock and install twrp.
Click to expand...
Click to collapse
it say can't modify system ..... - now way to install factory rom from fastboot
alltoolbox use fastboot

Well i think the last resource is trying to unbrick your device with EDL mode
But you'll have to physically open your phone
Once connected test-point and phone with usb cable you'll be able to see in device manager a new device
Use some metal tool like tweezers to connect the test points together
While holding test-points together connect your device to pc
After new device appeared in device manager you can release the test-points and continue
Press “refresh” in MiFlash tool
A new device should also appear
This means that everything is good and you've entered EDL mode
Then you'll have to flash phone
Here an example/tutorial
https://www.youtube.com/watch?v=BrEyAEXid_o

srepole said:
Well i think the last resource is trying to unbrick your device with EDL mode
But you'll have to physically open your phone
Once connected test-point and phone with usb cable you'll be able to see in device manager a new device
Use some metal tool like tweezers to connect the test points together
While holding test-points together connect your device to pc
After new device appeared in device manager you can release the test-points and continue
Press “refresh” in MiFlash tool
A new device should also appear
This means that everything is good and you've entered EDL mode
Then you'll have to flash phone
Here an example/tutorial
https://www.youtube.com/watch?v=BrEyAEXid_o
Click to expand...
Click to collapse
thx it worked <3

Pixel 3 XL stuck in fasboot "error boot prepare" after rooting attempt with Magisk

Pixel 3 XL stuck in fasboot "error boot prepare" after rooting attempt with Magisk
Ok so I spent the morning rooting my phone with a Magisk_patched.img made with Magisk Canary.
Now, my phone will not exit fastboot mode no matter what I do and gives the error "error boot prepare".
I have even tried to flash the original boot image back to the phone but I still get the same error after doing so.
PLEASE, help?
EDIT
After doing more digging, it seems my phone is not being recognized by fastboot because when I run the adb devices command, I get an empty list of devices.
I'm guessing this is the problem, but how to I get fastboot/adb to recognize my phone?

catass said:
Ok so I spent the morning rooting my phone with a Magisk_patched.img made with Magisk Canary.
Now, my phone will not exit fastboot mode no matter what I do and gives the error "error boot prepare".
I have even tried to flash the original boot image back to the phone but I still get the same error after doing so.
PLEASE, help?
EDIT
After doing more digging, it seems my phone is not being recognized by fastboot because when I run the adb devices command, I get an empty list of devices.
I'm guessing this is the problem, but how to I get fastboot/adb to recognize my phone?
Click to expand...
Click to collapse
I responded to you in the other thread as well, but just in case:
You need to put the fastboot files in the platform tools folder and CMD cd to that folder.
Then ADB reboot bootloader
You can remove the -w from the flash all batch file so you don't have to wipe, then run it.

crixley said:
I responded to you in the other thread as well, but just in case:
You need to put the fastboot files in the platform tools folder and CMD cd to that folder.
Then ADB reboot bootloader
You can remove the -w from the flash all batch file so you don't have to wipe, then run it.
Click to expand...
Click to collapse
OK but when I input the adb reboot bootloader I get an error back saying there is no device/emulator found.
Also, do I put the whole OTA folder I unzipped into the platform-tools directory or just a few select files? Or any at all for that matter... pulling my hair out here lol. Thanks for your time and help, though.

Below is what happened when I ran the flash-all.bat file after moving it and everything else included in the OTA into the platform-tools directory.
I ran it just by double clicking it and choosing run:
Sending 'bootloader_b' (8361 KB) OKAY [ 0.369s]
Writing 'bootloader_b' (bootloader) Flashing Pack version b4s4-0.2-6066691
(bootloader) xbl signature verify fail
FAILED (remote: 'Validate packed image fail')
fastboot: error: Command failed
Rebooting into bootloader OKAY [ 0.049s]
Finished. Total time: 0.051s
Sending 'radio_b' (73276 KB) OKAY [ 2.190s]
Writing 'radio_b' (bootloader) Flashing Pack version SSD:g670-00036-200114-B-6134202
(bootloader) Flashing partition modem_b
OKAY [ 0.371s]
Finished. Total time: 2.791s
Rebooting into bootloader OKAY [ 0.049s]
Finished. Total time: 0.050s
--------------------------------------------
Bootloader Version...: b1c1-0.2-6085603
Baseband Version.....: g670-00036-200114-B-6134202
Serial Number........: 92CY17WPW
--------------------------------------------
extracting android-info.txt (0 MB) to RAM...
Checking 'product' FAILED
Device product is 'crosshatch'.
Update requires 'bonito' or 'sargo'.
fastboot: error: requirements not met!
Press any key to exit...
PS- Also, I even tried downloading the ota for sargo and extracted the payload.bin file to get the boot.img for sargo and tried using that to boot back to stock ota but i still get stuck in fastboot after running the reboot command.
WTF.

Why would you try using things from a different device (are you sure your device is even a pixel 3 xl)? Seems your fastboot or drivers are not correct or you are using an incorrect image.

wangdaning said:
Why would you try using things from a different device (are you sure your device is even a pixel 3 xl)? Seems your fastboot or drivers are not correct or you are using an incorrect image.
Click to expand...
Click to collapse
Because when I tried flash-all.bat, at the bottom of the respond prompt it says something about current product is crosshatch and must be bonito or sargo(sp?). Take a look at my last post in this thread where i copy pasted what the command prompt returned me. It's near the bottom where it says it.
I interpreted that as having the wrong boot.img, so I downloaded bonito which is actually for the 3a XL hoping it would work but it didnt.
Also below is what the command prompt returns to me when I try adb reboot bootloader. I have a feeling if I can get things to where it recognizes a device when I run the adb reboot bootloader command, then my problems will be solved. I just have no idea on how to do so.
C:\Users\Dtbur\Downloads\platform-tools>adb reboot bootloader
error: no devices/emulators found

Update, new error.
So I downloaded the Pixel 3 XL OTA from FEB 2020 instead of the newest one from MARCH 2020.
Now, I can get out of fastboot for (for a second) to a screen that warns me about the bootloader being unlocked and not to store any sensitive data on the device, followed by the Google flash screen, BUT then back to fastboot mode.
The enter reason I got the first time after this happened was Enter reason: No valid boot slot.
SO... I tried fastboot flash boot_a boot.img to get the a slot flashed, as well.
That didn't work BUT now I get a new Enter reason: error booting boot.img.
Am I starting to get somewhere, or just making things worse?

If I were you I would connect, make sure device is recognized by fastboot, and try the crosshatch flash all again.

OK so I finally managed to get out of fastboot and flash a factory image.
I then patched with Magisk again to get root (worked this time). All I have done is flash the magisk_patched.img to my phone in fastboot and I seem to have gotten root after installing root checker.
Is this all that I need to do for root? On the root checker app it says: Superuser binary files not installed. What are Superuser binary files? Is this an issue? Everything else checks out in the root checker app.

can you advise how do you able to flash back to factory. I am having same issue.

Same issue on pixel 4
crixley said:
I responded to you in the other thread as well, but just in case:
You need to put the fastboot files in the platform tools folder and CMD cd to that folder.
Then ADB reboot bootloader
You can remove the -w from the flash all batch file so you don't have to wipe, then run it.
Click to expand...
Click to collapse
my pixel 4 is stuck on bootloader. "error boot prepare".
I did this on my Mac - > ./fastboot flash boot_a /Users/vladgolouschin/Downloads/Pixel/lineage-17.1-20201122-recovery-flame.img
Sending 'boot_a' (65536 KB) OKAY [ 1.550s]
Writing 'boot_a' OKAY [ 0.532s]
Finished. Total time: 2.372s
I tried also flashing boot without a. Also tried boot__a (this one returns error).
PLEASE HELP

Vlad_vog said:
my pixel 4 is stuck on bootloader. "error boot prepare".
I did this on my Mac - > ./fastboot flash boot_a /Users/vladgolouschin/Downloads/Pixel/lineage-17.1-20201122-recovery-flame.img
Sending 'boot_a' (65536 KB) OKAY [ 1.550s]
Writing 'boot_a' OKAY [ 0.532s]
Finished. Total time: 2.372s
I tried also flashing boot without a. Also tried boot__a (this one returns error).
PLEASE HELP
Click to expand...
Click to collapse
Try boot b as well that might help

Hi, I know this is a crazy old thread, but I'd like to share my fix for this:
First, this usually happens if you're playing around with Magisk and do "Reboot to EDL" without knowing what that does. Or any other tool to reboots your device in a silly manner and messes up the default partition it's living on. So, you then find yourself trapped in reboot/fastboot land. The bottom line is:
You get an error that says "error boot prepare" at the bottom of your screen.
To Fix:
1. Connect device to machine with adb/fastboot/etc
2. Type: fastboot set_active b (Or "a" - whatever the OPPOSITE is of what it's currently set to)
3. Type: fastboot reboot --slot b
*You will likely be brought to a broken loader window with the Android-Dude opened up, ignore it and type:
4. Type: adb reboot bootloader
5. Select Normal Start-Up after making sure your Boot slot is set to "b" (or "a")
6. After selecting Reboot to system and you should be set.
Key Take Aways:
If your phone ever gets stuck in a weird boot loop that all the sudden NOTHING works, including recovery mode, etc.. it's likely just looking on the wrong a/b partition and just needs a little guidance on where home is, via "set_active".
Thank You For Coming To My NED Talk.
Hope This Helps!
-DANNO

arfarfdan said:
Hi, I know this is a crazy old thread, but I'd like to share my fix for this:
First, this usually happens if you're playing around with Magisk and do "Reboot to EDL" without knowing what that does. Or any other tool to reboots your device in a silly manner and messes up the default partition it's living on. So, you then find yourself trapped in reboot/fastboot land. The bottom line is:
You get an error that says "error boot prepare" at the bottom of your screen.
To Fix:
1. Connect device to machine with adb/fastboot/etc
2. Type: fastboot set_active b (Or "a" - whatever the OPPOSITE is of what it's currently set to)
3. Type: fastboot reboot --slot b
*You will likely be brought to a broken loader window with the Android-Dude opened up, ignore it and type:
4. Type: adb reboot bootloader
5. Select Normal Start-Up after making sure your Boot slot is set to "b" (or "a")
6. After selecting Reboot to system and you should be set.
Key Take Aways:
If your phone ever gets stuck in a weird boot loop that all the sudden NOTHING works, including recovery mode, etc.. it's likely just looking on the wrong a/b partition and just needs a little guidance on where home is, via "set_active".
Thank You For Coming To My NED Talk.
Hope This Helps!
-DANNO
Click to expand...
Click to collapse
So I finished step 4, and I assumed for step five on my phone it said "reboot bootloader" instead of "error boot prepare" and hit "Start" on the power button. Now it is loading by showing the Google logo, will my phone restart normally once it finished or will it show the bootloader screen again? plus this is taking a long time so far 5=10 minutes will it be okay? My apologies in advance I am very new to this

arfarfdan said:
Hi, I know this is a crazy old thread, but I'd like to share my fix for this:
First, this usually happens if you're playing around with Magisk and do "Reboot to EDL" without knowing what that does. Or any other tool to reboots your device in a silly manner and messes up the default partition it's living on. So, you then find yourself trapped in reboot/fastboot land. The bottom line is:
You get an error that says "error boot prepare" at the bottom of your screen.
To Fix:
1. Connect device to machine with adb/fastboot/etc
2. Type: fastboot set_active b (Or "a" - whatever the OPPOSITE is of what it's currently set to)
3. Type: fastboot reboot --slot b
*You will likely be brought to a broken loader window with the Android-Dude opened up, ignore it and type:
4. Type: adb reboot bootloader
5. Select Normal Start-Up after making sure your Boot slot is set to "b" (or "a")
6. After selecting Reboot to system and you should be set.
Key Take Aways:
If your phone ever gets stuck in a weird boot loop that all the sudden NOTHING works, including recovery mode, etc.. it's likely just looking on the wrong a/b partition and just needs a little guidance on where home is, via "set_active".
Thank You For Coming To My NED Talk.
Hope This Helps!
-DANNO
Click to expand...
Click to collapse
Hi this is my problem, I have tried to downgrade the android system of my pixel 3aXL, from android 12 to android 11 by following this tutorial: https://9to5google.com/2021/10/21/how-to-downgrade-from- android-12-to-android-11-on-google-pixel /
Unfortunately I'm hopelessly stuck in the "Fastboot Mode" loop. I have downloaded the "platform-tools_r31.0.3-windows" tool, I have downloaded, unzipped and pasted the content of the latest android image for my 3aXL pixel "bonito-sp1a.210812.016.a1-factory-8a51e8a7" (android 12), In the folder "platform-tools", then I open the command window "cmd" and run the command "adb reboot bootloader", but it tells me the following: "* daemon not running; starting now at tcp: 5037 * daemon started successfully error: no devices / emulators found ", and when I execute the command" flash-all ", it keeps thinking:" <waiting for any device> ", while in the section of" Fastboot Mode "in the option" Enter reason " it says: "reboot bootloader" I have tried the factory reset, "adroid flash tool" and nothing works, I would greatly appreciate your help, please!
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Lenovo P2 stuck in "Fast boot" menu. Bricked?

I have a Lenovo P2, unrooted, on stock Android, with a 256mb micro SD card. It hasn't been unlocked/flashed/rooted in any way apart from Developer Options to allow ADB.
A couple of days ago the phone started to lag and lock up, and then rebooted into "AP Fastboot Flash Mode (Secure)" menu. The only options are Start/Barcodes/Power Off.
The Start and Power Off/On options simply reboot back to the same screen after a couple of seconds. It won't boot back into Android with any combination of volume up/down/power buttons, or offer me any other options such as recovery or clear cache etc.
I've tried rebooting with/without the SD card - it makes no difference.
The phone still appears to be recognised by ADB when I connect it to a laptop - it appears in 'fastboot devices' - but I still can't get it to exit fastboot and boot back into Android with any ADB command.
I've tried downloading Reiboot and "15 second adb" toolkits which claim to exit fastboot mode, but without success.
I'm assuming the bootloader is corrupted.
Can anyone please point me towards any possible action for fixing it, or is it bricked?
Many thanks.
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The thing you are on now is the bootloader...
What you did is probably soft bricked the phone.
What did you perform with adb?

If your rom is not booting you might need to reinstall it.

Keno_I said:
The thing you are on now is the bootloader...
What you did is probably soft bricked the phone.
What did you perform with adb?
Click to expand...
Click to collapse
Here's what I've tried with ADB - the phone seems to be connected as evidenced by "fastboot devices", but I don't know what to do now. "Fastboot reboot" just brings me back to the same Fastboot screen in my original post, as does holding down vol+/vol-/power for several seconds.
I successfully unlocked/flashed a ZTE San Francisco Blade back in the day, so I don't mind trying to flash this P2 if that's the answer and you can point me towards a noob-friendly guide, please.

Reinstall the stock rom from fastboot

@Kenora_I
To try and reinstall stock, I'm following the instructions here --> https://forum.xda-developers.com/t/lenovo-p2-fastboot-files-of-every-stock-firmware.3649914/
and have downloaded all the firmware files linked on that page, ie https://www.androidfilehost.com/?w=files&flid=205781
Do I need to unlock the bootloader first?
Well, when I tried to "fastboot oem unlock", I got
fastboot oem unlock
...
FAILED (remote: oem unlock error: partition tampered
I then tried the Flash commands given, and got this error;
Fastboot flash system systemchunk0.img
target reported max download size of 536870912 bytes
sending 'system' (260121 KB)...
OKAY [ 9.303s]
writing 'system'...
FAILED (remote: Not official valid sparse image)
finished. total time: 9.379s
I got this with every set of firmware files on the download link. Am I trying to use the wrong firmware images?
Thanks for any tips and suggestions.

bigajm said:
@Kenora_I
To try and reinstall stock, I'm following the instructions here --> https://forum.xda-developers.com/t/lenovo-p2-fastboot-files-of-every-stock-firmware.3649914/
and have downloaded all the firmware files linked on that page, ie https://www.androidfilehost.com/?w=files&flid=205781
Do I need to unlock the bootloader first?
Well, when I tried to "fastboot oem unlock", I got
fastboot oem unlock
...
FAILED (remote: oem unlock error: partition tampered
I then tried the Flash commands given, and got this error;
Fastboot flash system systemchunk0.img
target reported max download size of 536870912 bytes
sending 'system' (260121 KB)...
OKAY [ 9.303s]
writing 'system'...
FAILED (remote: Not official valid sparse image)
finished. total time: 9.379s
I got this with every set of firmware files on the download link. Am I trying to use the wrong firmware images?
Thanks for any tips and suggestions.
Click to expand...
Click to collapse
You have to find and flash a valid flash image, try with the same version you were installed on

Can someone provide me with a twrp restore file? I tried to flash the stock rom but the bat file that came with it tampered with some files and I can't even boot into the stock rom

Question Is it ok to skip an update using the android flash tool

So basically I haven't updated since android 13 came out. Last month I saw that the monthly patch had arrived but the android flash tool didn't seem to have it. I haven't been bothered enoguh to check again since then but I now see that they builds aren't separated like they used to be and there's only a Android 13 option. I am currently on TP1A.220624.021, and Andrioid Flash Tool is offering TP1A.221005.002.

Divine Bicycle said:
So basically I haven't updated since android 13 came out. Last month I saw that the monthly patch had arrived but the android flash tool didn't seem to have it. I haven't been bothered enoguh to check again since then but I now see that they builds aren't separated like they used to be and there's only a Android 13 option. I am currently on TP1A.220624.021, and Andrioid Flash Tool is offering TP1A.221005.002.
Click to expand...
Click to collapse
Yeah, it's fine to just update to the latest. As a reminder, make sure you have the A13 bootloader flashed to both slots before doing anything, if you haven't already,

Lughnasadh said:
Yeah, it's fine to just update to the latest. As a reminder, make sure you have the A13 bootloader flashed to both slots before doing anything, if you haven't already,
Click to expand...
Click to collapse
Ok, as for having both slots flashed, in not entirely sure if they are haha. I had a few issues updating to Android 13 as listed here, so I'm assuming they are both flashed.

Divine Bicycle said:
Ok, as for having both slots flashed, in not entirely sure if they are haha. I had a few issues updating to Android 13 as listed here, so I'm assuming they are both flashed.
Click to expand...
Click to collapse
Reading through that thread it doesn't sound like you did as Android Flash Tool doesn't flash to both slots, even when force flash partitions is selected.
Follow the guide in the link below to flash the A13 bootloader to the opposite slot.
🛑❗⚠️ WARNING! Read this before your initial upgrade to Android 13!⚠️❗🛑
***Note: THIS IS NOT A ROOT GUIDE. For updating and root instructions, check out my guide here.*** From the Pixel Images page: This applies to ALL Tensor devices, regardless of whether or not you're rooted! What this means: Once Android 13...
forum.xda-developers.com

Lughnasadh said:
Reading through that thread it doesn't sound like you did as Android Flash Tool doesn't flash to both slots, even when force flash partitions is selected.
Follow the guide in the link below to flash the A13 bootloader to the opposite slot.
🛑❗⚠️ WARNING! Read this before your initial upgrade to Android 13!⚠️❗🛑
***Note: THIS IS NOT A ROOT GUIDE. For updating and root instructions, check out my guide here.*** From the Pixel Images page: This applies to ALL Tensor devices, regardless of whether or not you're rooted! What this means: Once Android 13...
forum.xda-developers.com
Click to expand...
Click to collapse
Sorry for the *very* late response. When I was trying using ADB and ```flash-all.bat```, I think the bootloader flashed successfully. However I will try the instructions at the bottom of the page you linked to check the bootloader version.

Ok, so I've just checked. The bootloader is the same version on both slots:
Microsoft Windows [Version 10.0.19044.2130]
(c) Microsoft Corporation. All rights reserved.
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>adb reboot bootloader
* daemon not running; starting now at tcp:5037
* daemon started successfully
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot devices
1C101FDEE009NE fastboot
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar current-slot
current-slot: a
Finished. Total time: 0.002s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar version-bootloader
version-bootloader: slider-1.2-8739948
Finished. Total time: 0.005s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot --set-active=b
Setting current slot to 'b' OKAY [ 0.111s]
Finished. Total time: 0.116s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar current-slot
current-slot: b
Finished. Total time: 0.002s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>adb reboot bootloader
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar bersion-bootlaoder
getvar:bersion-bootlaoder FAILED (remote: 'variable (bersion-bootlaoder) not found')
Finished. Total time: 0.008s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar bersion-bootloader
getvar:bersion-bootloader FAILED (remote: 'variable (bersion-bootloader) not found')
Finished. Total time: 0.011s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar version-bootloader
version-bootloader: slider-1.2-8739948
Finished. Total time: 0.003s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot --set-active a
fastboot: usage: unknown command a
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot --set-active=a
Setting current slot to 'a' OKAY [ 0.125s]
Finished. Total time: 0.133s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot getvar current-slot
current-slot: a
Finished. Total time: 0.002s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>fastboot continue
Resuming boot OKAY [ 0.036s]
Finished. Total time: 0.051s
C:\Users\$USER\Downloads\platform-tools_r33.0.2-windows\platform-tools>
Click to expand...
Click to collapse
If you ignore my typos, then you can see that both slots are on bootloader version 'slider-1.2-8739948'. What steps should I take to update to the latest system version now? Just update through the Android Flash Tool?

Divine Bicycle said:
Ok, so I've just checked. The bootloader is the same version on both slots:
If you ignore my typos, then you can see that both slots are on bootloader version 'slider-1.2-8739948'. What steps should I take to update to the latest system version now? Just update through the Android Flash Tool?
Click to expand...
Click to collapse
Updating via Android Flash Tool is fine. You can also use the Pixel Flasher.

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Thank you for that advice, I am now up to date and using Kirisakura's kernel.