Database Users

[Q] Nexus 7 bricked while sending system via SDK

Hi all,
I updated my nexus 7 to 4.2 but decided to revert back to 4.1.2. So I downloaded SDK and followed the instruction by 2defmouze to restore to stock image for 4.1.2 but now it is stuck at the message sending 'system' <446268 KB> in the cmd window and nexus 7 is not responding in anyway with the volume and on/off buttons. The message has been there for more than an hour. Is there anyway to help to restore it back to anything operational?
Thanks for the help!

Same Problem
quastenflosser said:
Hi all,
I updated my nexus 7 to 4.2 but decided to revert back to 4.1.2. So I downloaded SDK and followed the instruction by 2defmouze to restore to stock image for 4.1.2 but now it is stuck at the message sending 'system' <446268 KB> in the cmd window and nexus 7 is not responding in anyway with the volume and on/off buttons. The message has been there for more than an hour. Is there anyway to help to restore it back to anything operational?
Thanks for the help!
Click to expand...
Click to collapse
Same Problem here.
Trying to flash Stock Rom 4.2 from google servers. Tried with the toolkit (Step9) first and then via flash-all.bat in cmd window.
No results, stuck @ "sending system". Before it stucks it says in the cmd window "archive doesn't contain 'boot.sig', 'Recovery.sig' and 'system.sig'.
Please anyone knows what to do and could help us fellas?
Thanks from Germany,
Trip

i have the exact same problem as the above poster except my Nexus is bricked, well not actually bricked but a bad flash and i ended up erasing data and trying to flash stock image JXO 54K, ,this is my second attempt to do this, yesterday ive no idea what went wrong, this evening ive got as far as "sending system 446268 KB" and its just stuck on that now for ages, i did notice that it said
archive does not contain "boot -sig"
archive does not contain "recovery-sig"
archive does not contain "system-sig"
so am i to assume this didnt flash properly or what could i be doing wrong?

jonny68 said:
i have the exact same problem as the above poster except my Nexus is bricked, well not actually bricked but a bad flash and i ended up erasing data and trying to flash stock image JXO 54K, ,this is my second attempt to do this, yesterday ive no idea what went wrong, this evening ive got as far as "sending system 446268 KB" and its just stuck on that now for ages, i did notice that it said
archive does not contain "boot -sig"
archive does not contain "recovery-sig"
archive does not contain "system-sig"
so am i to assume this didnt flash properly or what could i be doing wrong?
Click to expand...
Click to collapse
The sticky thread indicates it's supposed to say that. You can try flashing the images manually also.
Sent from my SGH-I777 using xda premium

korockinout13 said:
The sticky thread indicates it's supposed to say that. You can try flashing the images manually also.
Sent from my SGH-I777 using xda premium
Click to expand...
Click to collapse
Ok that's fine but it wouldn't move on from where it said "sending system", how long is it supposed to stay on that, after half an hour I gave up and me Nexus is still dead.
Another thing when I boot into fastboot mode and click on recovery it won't appear, instead I see am image of a "dead android",
Sent from my GT-I9300 using xda app-developers app

jonny68 said:
Ok that's fine but it wouldn't move on from where it said "sending system", how long is it supposed to stay on that, after half an hour I gave up and me Nexus is still dead.
Another thing when I boot into fastboot mode and click on recovery it won't appear, instead I see am image of a "dead android",
Sent from my GT-I9300 using xda app-developers app
Click to expand...
Click to collapse
That's the stock recovery. Try flashing either CWM or TWRP via fastboot (I recommend TWRP), that should get you back into a usable recovery. From there you can push a flashable zip of some kind to it and flash it through recovery.
As for the original problem, have you checked either the MD5 or SHA1 checksum to make sure it was a good download? Have you tried downloading again? Not sure what else could be the issue here.

Anybody able to figure out why their Nexus became unresponsive. or how to get it to work?
Having the same issue. When flashing my Nexus was bricked during sending system does the same everytime I try to flash it.

rdelarosa3 said:
Anybody able to figure out why their Nexus became unresponsive. or how to get it to work?
Having the same issue. When flashing my Nexus was bricked during sending system does the same everytime I try to flash it.
Click to expand...
Click to collapse
A Nexus 7 is not "bricked" if it has a (correctly functioning) bootloader or a (working) custom recovery. It might be OK to call this "soft-bricked", though.
If you have a flaky connection between the PC and the tablet, the most likely place for a communication error to occur is when a whole lot of data is transferred. For flashing via fastboot, this usually tends to be the system partition, simply because it is tremendously larger than anything else which is flashed via fastboot. (The problem could also be on the tablet - a communication data corruption problem is only one of several possible hazards.)
So, there are at least two workarounds:
(1) avoid flashing where the file must be transferred (fastboot or adb sideload) - choose a "recovery-flashable" ROM and use the recovery to perform flashing of /system. Note that it is reported that you can NOT flash factory "system.img" files as a raw partition - apparently they are in a sparse ext4 image file format that bootloader (fastboot) understands, but are not the same as a block-by-block copy of an ext4 filesystem. So, we are talking about a "custom ROM" here, not a pure factory ROM.
(2) switch to a different cable / USB port on the PC, etc and see if you get a different result flashing the system.img file using fastboot.
(Note that if you experience stuff like this - strangeness in transferring files "across the wire", you should avoid flashing the bootloader using fastboot under any circumstances using the same setup - it is simply too dangerous to make a mistake with the bootloader. There are other ways to update the bootloader that are far, far, safer.)
good luck

[Q] Unable to Flash Nexus 7

hello everyone..
In serious need of help here and hope someone can help..
Due to the massive battery drain issue I have been having, I tried to flash the original stock rom on my nexus 7 and
things have gone downhill really bad..
in the past, I flashed using this guide (http://forum.xda-developers.com/showthread.php?t=1907796)
without any problems but last night.. I encountered errors when trying to flash the bootloader
and radio IMG files.. neeedless to say when it comes to flashing the rom in, it came out with errors and my nexus remain OS-less
the errors when trying to flash the bootloader and radio are
"failed (command write failed (Invalid Argument))"
can anyone help me?
p.s :- if anyone can even suggest me a easier way to flash custom roms in and so forth, your suggestion will be most welcomed..
also, I did try wug's rootkit plus the nexus 7 toolkit or something, both came out errors too when too do any flashing in relating to
the bootloader or system.. thanks

Why were you trying to flash the bootloader? Were you trying to update to 4.18?

Username invalid said:
Why were you trying to flash the bootloader? Were you trying to update to 4.18?
Click to expand...
Click to collapse
actually, my bootloader boots fine, it shows tilapia 4.18.
so does this mean I dont have to flash it?
if I dont have to flash the bootloader, do I have to flash the radio?
sorry, kind of a noob in these things..

Anyway, is it normal for the bootloader flash attempt to fail?

hamiksu said:
Anyway, is it normal for the bootloader flash attempt to fail?
Click to expand...
Click to collapse
No, it's not normal for it to fail.
You really don't need to flash either unless one of them is screwed up or you are upgrading to a newer version. Bootloader flashes are risky anyway. To avoid flashing them, you can either remove code from the updater script or remove them from the factory image files entirely.

korockinout13 said:
No, it's not normal for it to fail.
You really don't need to flash either unless one of them is screwed up or you are upgrading to a newer version. Bootloader flashes are risky anyway. To avoid flashing them, you can either remove code from the updater script or remove them from the factory image files entirely.
Click to expand...
Click to collapse
hmm, ok..
then I will go back home and do the system flashing and try and post out the errors it stated there..
really hope to get my nexus back on line...

This is what I get when I tried to flash the image
Hope someone can guide me on what to do next.

hamiksu said:
This is what I get when I tried to flash the image
Hope someone can guide me on what to do next.
Click to expand...
Click to collapse
Try to unlock your bootloader before flashing image with the command:
fastboot oem unlock

ameinild said:
Try to unlock your bootloader before flashing image with the command:
fastboot oem unlock
Click to expand...
Click to collapse
it says my bootloader is already unlocked

hamiksu said:
it says my bootloader is already unlocked
Click to expand...
Click to collapse
Then it sounds like something happened to your system partition that should not have happened.
Are you sure the system image you're trying to flash is valid, do the md5 sums match?
How about flashing another system image?
Or flash a custom recovery, and install a new ROM from there?

ameinild said:
Try to unlock your bootloader before flashing image with the command:
fastboot oem unlock
Click to expand...
Click to collapse
ameinild said:
Then it sounds like something happened to your system partition that should not have happened. Sorry, can't help you there...
Click to expand...
Click to collapse
meaning my system partition is screwed?
anyone knows how to go around this problem?
p.s :- anyway ameinild, thanks for trying to help

hamiksu said:
p.s :- anyway ameinild, thanks for trying to help
Click to expand...
Click to collapse
I edited my post with some more suggestions to try first

ameinild said:
I edited my post with some more suggestions to try first
Click to expand...
Click to collapse
yup, the image i tried a few.. even tried stock rom image.
tried both nexus 7 toolkit
as well as wugs nexus root tool kit.
they all seem to encounter problems when trying to "push" the rom images in or something.
is there a way to like format the entire thing and install from scratch>?

hamiksu said:
is there a way to like format the entire thing and install from scratch>?
Click to expand...
Click to collapse
Sorry, I can't really find anything for the N7... Hope someone else can chime in.

ameinild said:
Sorry, I can't really find anything for the N7... Hope someone else can chime in.
Click to expand...
Click to collapse
Yea, I hope someone will pop in and be my guardian angel too..
Thanks again, Ameinild

tried to flash stock rom using wug's rootkit..
this is what happens...

hamiksu said:
tried to flash stock rom using wug's rootkit..
this is what happens...
Click to expand...
Click to collapse
As a rule, don't do anything with a toolkit that you don't know how to do yourself with the relevant fastboot or ADB commands. It has a nasty tendency of leaving you in a lurch.
I noticed that your last run of Wug's toolkit did claim to successfully flash your recovery. Have you been able to access it from the fastboot menu on the device? If so, that's a major step forward.
Perhaps most importantly (based on your mentioning of tilapia earlier), are you 100% certain that you are trying to flash the factory image for your model of the Nexus 7?

Rirere said:
As a rule, don't do anything with a toolkit that you don't know how to do yourself with the relevant fastboot or ADB commands. It has a nasty tendency of leaving you in a lurch.
I noticed that your last run of Wug's toolkit did claim to successfully flash your recovery. Have you been able to access it from the fastboot menu on the device? If so, that's a major step forward.
Perhaps most importantly (based on your mentioning of tilapia earlier), are you 100% certain that you are trying to flash the factory image for your model of the Nexus 7?
Click to expand...
Click to collapse
Yes, I am absolutely sure it is the image for my nexus 7.. which is 3g/wifi model, not just wifi only..
image file is downloaded using wug's rootkit too..
file name = nakasig-jdq39-factory-0798439d.tgz
as the snapshot shows.. it keeps showing failed when "sending system"
please tell me you have an idea on why it keeps failing there...
*crosses fingers*
p.s :- after that (numerous) wug's toolkit attempt to flash back stock rom, I tried booting to recovery and it shows the android on its back with a red exclamation mark on its open body chasis

I'm assuming you haven't tried this yet, if you have tried this just ignore.
1 - Download - http://techerrata.com/file/twrp2/grouper/openrecovery-twrp-2.6.0.0-grouper.img
2 - fastboot flash recovery openrecovery-twrp-2.6.0.0-grouper.img
If flashes fine:
Power off Nexus, Hold Volume down and Power on, keep holding power down until you get to recovery.
Then:
Either - Get a USB OTG and put a ROM on a USB Stick, go to "install" - "Use external storage" find the rom and flash it.
or
Plug in to PC whilst in recovery, - Mount Storage - Now the Nexus should pop up on PC, Drag ROM to Nexus. Unmount and then try to flash.
Let me know how you get on with this.
Regards.

hamiksu said:
Yes, I am absolutely sure it is the image for my nexus 7.. which is 3g/wifi model, not just wifi only..
image file is downloaded using wug's rootkit too..
file name = nakasig-jdq39-factory-0798439d.tgz
as the snapshot shows.. it keeps showing failed when "sending system"
please tell me you have an idea on why it keeps failing there...
*crosses fingers*
p.s :- after that (numerous) wug's toolkit attempt to flash back stock rom, I tried booting to recovery and it shows the android on its back with a red exclamation mark on its open body chasis
Click to expand...
Click to collapse
That's because you have stock recovery installed now and it's unable to verify that your device is in working order, hence the red mark. Find TWRP for your device, download the .img and try to flash it with fastboot flash recovery <path-to-recovery.img>. Since you can at least get into a recovery, it's possible you'll be able to use onboard recovery tools to see what state your internal partitions are in.
Until there's a little more info available, there's nothing I can say that's not pure conjecture.

[Q] [Softbricked[ Help! Accidentally flashed recovery image to boot partition...

Ok, so I unlocked my Nexus 7 (2013). Then I was trying to root it and after booting it into the bootloader, I typed:
"fastboot flash boot twrp.img" I was supposed to type "fastboot flash recovery twrp.img"
PLEASE HELP! My device boots into TWRP EXCLUSIVELY!
How do I get my os back? Is it gone? Can this be easily fixed?
I will be eternally in your debt if you can help me out, I feel so stupid, this is the first time I've bricked something and I've been unlocking, rooting, flashing android devices since my G1, then my Nexus One, which I even repartitioned the system partition so it could fit 4.2.2 Cm 10. I also unlocked, my touch pad and flashed cm dual booting with web os. Unlocking/rooting/flashingcustomrecovery on my Nexus 4 was a one click though so I guess I was rusty.
Edit: messed up a bracket in the title... Great...

I am not an expert, but I think you'll be fine flashing a ROM image as that will install the boot files. I'd get confirmation though.
But no crying!
Sent from my Nexus 7 using xda app-developers app

Coronado is dead said:
I am not an expert, but I think you'll be fine flashing a ROM image as that will install the boot files. I'd get confirmation though.
But no crying!
Sent from my Nexus 7 using xda app-developers app
Click to expand...
Click to collapse
I don't have a rom image on my device though? How can I get one on there when I can only get into the bootloader or recovery...
Thanks for responding! I hope I can get this fixed...

In TWRP I think there is a way to mount USB and transfer it over. Maybe under advanced?
Sent from my Nexus 7 using xda app-developers app

Hmm maybe someone could make a .zip file to flash the boot loader in twrp

And there is always the option of getting the factory image from Google and using it over USB with fastboot on. Clean slate.
Sent from my Nexus 7 using xda app-developers app
---------- Post added at 12:54 AM ---------- Previous post was at 12:53 AM ----------
How to factory image restore:
http://www.androidpolice.com/2013/0...stock-using-a-full-factory-image-and-root-it/
Sent from my Nexus 7 using xda app-developers app

Flash any custom kernel, as it stands as "boot" partition.
Or just flash the boot image manually from the factory image:
Code:
fastboot flash boot boot.img
Then flash TWRP like normally you did before:
Code:
fastboot flash recovery recovery.img
Sent from my Galaxy S3 i9300

If you can go to bootloader or TWP, then you have many choices to fix your Nexus.
1. Download a factory image from Google, boot to bootloader and flash the whole thing. And remember to download the right factory image for Nexus 7(2013) (flo or razor). Check MD5 after downloading to make sure everything is OK. If you dont know how to flash a factory image, there is a couple topics in General and Q&A to assist you.
2. Or you can download a custom kernel in the Original Development area. THen boot to TWRP, use ADB to push the custom kernel file to your device, then install it by TWRP.
3. You can use a toolkit which I dont recommend.

Ok, so in my frantic attempts to fix this, I was trying to get adb sideload to work and was told to try and do a factory reset and wipe system and internal storage. I did this and still can't figure out how to get sideloading to work, I'm trying adb sideload rom.zip, and adb push rom.zip /sdcard which is what I read from another thread, but have not been able to get the factory image over.
Also, when I go to flash the .img that came with the factory image, fasboot says:
<code>sending 'boot' <2100 KB>....
OKAY [ 0.080s]
writing 'boot'...
FAILED <remote: image is not a boot image>
finished total time: 0.090s
</code>

OH GOD!
Download the Factory Image of Android 4.3 for ‘razor’ Nexus 7 tablet from here.
> this download contains the full system, bootloader, recovery and kernel boot img files.
Extract the ‘tgz’ factory image archive and place all contents into a single folder.
Next, you will need to edit a file so that your data will not be wiped. If you want to wipe data then you should skip this step.
> so, edit the ‘flash-all.bat’ for Windows or ‘flash-all.sh’ for Mac / Linux using a text editing tool:
- you will need to edit the ‘fastboot update’ command so that it will transform from ‘fastboot -w update image-razor-jss15j.zip’ into ‘fastboot update image-razor-jss15j.zip’. You will basically need to delete the ‘-w’ text, which is the command that tells fastboot to wipe data from your device.
- continue to the next step when you’re sure that the ‘-w’ text has been removed.
Now, power off your Nexus 7 2013 tablet.
Boot it into Bootloader Mode.
Connect it with your computer via USB cable.
Run the ‘flash-all’ script and wait for the factory image to be successfully installed.
Ok, so I did this, I downloaded the factory image, and ran the flash all command and that failed and now it's hard bricked! here is a screenshot of what the flash-all command output...
I will seriously pay someone to help me fix this at this point! I'm freaking out!
http://imgur.com/XsAJ4FV

mattj7 said:
Also, when I go to flash the .img that came with the factory image, fasboot says:
<code>sending 'boot' <2100 KB>....
OKAY [ 0.080s]
writing 'boot'...
FAILED <remote: image is not a boot image>
finished total time: 0.090s
</code>
Click to expand...
Click to collapse
You must have done something wrong. The boot.img that came with the factory restore is 6880KB not 2100KB.
Take things slow. You are still in a place where you can recover. If you make too many mistakes, you can make it even harder to recover.

Never mind, the problem had been solved.

sfhub said:
You must have done something wrong. The boot.img that came with the factory restore is 6880KB not 2100KB.
Take things slow. You are still in a place where you can recover. If you make too many mistakes, you can make it even harder to recover.
Click to expand...
Click to collapse
Yes, it was the factory image for the first nexus 7, I just ran the flash all on the right one and now I can boot just fine
WHEW
Ok guys, great job everyone!
Now I'm going to figure out if the custom recovery is still there, it probably isn't, and I can just flash it with fastboot now.

slamdunksaliby said:
Hmm maybe someone could make a .zip file to flash the boot loader in twrp
Click to expand...
Click to collapse
The only way is by the fastboot way, because it's an .img file
And don't forget that you can find all files that you need to this thread => [Index] REPO for all you need for your nexus 7 FLO (2013)

philos64 said:
The only way is by the fastboot way, because it's an .img file
]
Click to expand...
Click to collapse
Well, that is untrue. The bootloader .img is just a collection of other .img that get flashed to their respective partitions, such as aboot, sbl1, sbl2, sbl2b, sbl3, sbl3b, and rpm. :good:

Nburnes said:
Well, that is untrue. The bootloader .img is just a collection of other .img that get flashed to their respective partitions, such as aboot, sbl1, sbl2, sbl2b, sbl3, sbl3b, and rpm. :good:
Click to expand...
Click to collapse
Please I don't agree when you say it's untrue.
For most users, this is the easiest solution for this.
If you do a survey, I would like to see how many people know that you can flash by other means

philos64 said:
Please I don't agree when you say it's untrue.
For most users, this is the easiest solution for this.
If you do a survey, I would like to see how many people know that you can flash by other means
Click to expand...
Click to collapse
Well, I know you can flash by other means.
I don't think he said it was the easiest to flash from twrp. He just said it could be done, which it can.
I think far more people have done it through recovery than have known they have done it.
Everyone who flashes the JSS15J OTA will get the bootloader flashed in the way he described. If twrp is using the same kernel as stock recovery, then it can be done in twrp also.

philos64 said:
Please I don't agree when you say it's untrue.
For most users, this is the easiest solution for this.
If you do a survey, I would like to see how many people know that you can flash by other means
Click to expand...
Click to collapse
I'm not personally attacking you or anything and I am sorry if you took it that way.
I'm just stating that saying fastboot is the only way is not true. The partitions can easily be flashed through CWM/TWRP as they have been with, from my experience, Galaxy Nexus, Nexus 4, and Nexus 7 (2012).

sfhub said:
Well, I know you can flash by other means.
I don't think he said it was the easiest to flash from twrp. He just said it could be done, which it can.
I think far more people have done it through recovery than have known they have done it.
Everyone who flashes the JSS15J OTA will get the bootloader flashed in the way he described. If twrp is using the same kernel as stock recovery, then it can be done in twrp also.
Click to expand...
Click to collapse
Nburnes said:
I'm not personally attacking you or anything and I am sorry if you took it that way.
I'm just stating that saying fastboot is the only way is not true. The partitions can easily be flashed through CWM/TWRP as they have been with, from my experience, Galaxy Nexus, Nexus 4, and Nexus 7 (2012).
Click to expand...
Click to collapse
No problem
But as I said, almost users don't flashed by the way of the partitions.
It would be better to say the easiest way
Sent from my HTC One using Tapatalk 4 between sky and earth

[Q] Flash new bootloader

Hi there
So, I can't enter recovery when I go into the bootloader to do so. I click 'recovery' and it just shows the black start up screen with the google logo. And nothing else happens. Ever. I reflashed recovery, and was able to get into recovery to install a new rom. However, after that one time, I was once again, unable to enter recovery. Now I haven't the time to be reflashing recovery just to get into it every time I want to, so I looked for a solution.
I did some reading around and apparently it's the bootloader version I'm using. (According to post five in this thread, and my assumption that I'm having a similar problem to this thread's OP.
Now if that is the solution to my problem as well, I need a bit of help. I can't find a file for the old bootloader, nor do I have any idea how to flash an old bootloader. (And please know, I wouldn't be asking had a google search not come up fruitless).
EDIT: Would flashing a completely stock 4.4.2 image update my bootloader? I wouldn't mind doing that, rooting that, and then just installing purity rom or something.

Zorigo said:
Hi there
So, I can't enter recovery when I go into the bootloader to do so. I click 'recovery' and it just shows the black start up screen with the google logo. And nothing else happens. Ever. I reflashed recovery, and was able to get into recovery to install a new rom. However, after that one time, I was once again, unable to enter recovery. Now I haven't the time to be reflashing recovery just to get into it every time I want to, so I looked for a solution.
I did some reading around and apparently it's the bootloader version I'm using. (According to post five in this thread, and my assumption that I'm having a similar problem to this thread's OP.
Now if that is the solution to my problem as well, I need a bit of help. I can't find a file for the old bootloader, nor do I have any idea how to flash an old bootloader. (And please know, I wouldn't be asking had a google search not come up fruitless).
EDIT: Would flashing a completely stock 4.4.2 image update my bootloader? I wouldn't mind doing that, rooting that, and then just installing purity rom or something.
Click to expand...
Click to collapse
Hi Mate ,
I been looking for the same but for other reasons , to flash it is not too difficult for what i see in this thread tell how to do it manually:
http://forum.xda-developers.com/showthread.php?t=2150251
or
http://forum.xda-developers.com/showthread.php?t=2417097
in the first one they even have a zip version of it which should install like any other zip from recovery
Also you can use a tool kit like NRT which makes life a lot easier once you got the bootloader image...(advance utilities)
http://forum.xda-developers.com/showthread.php?t=1766475
My problem is that i do not know where can i get the different bootloader images...
To your question i think so , bootloader should be included in the factory image......downloading one to confirm.
also check this information
http://trendblog.net/flash-android-4-4-factory-images-nexus-4-nexus-7/

MAX 404 said:
.snip.
My problem is that i do not know where can i get the different bootloader images...
.snip.
Click to expand...
Click to collapse
If you download the factory image, extract it, the bootloader is in the folder. Then just flash through fastboot. Just make sure you download the correct bootloader for your device

For anyone reading this thread, my solution was too move to the 4.32 bootloader from JWR66V. I flashed the .img file from this thread using Wugfresh's fantastic toolkit. (linked to in the 2nd post of this thread).

Zorigo said:
For anyone reading this thread, my solution was too move to the 4.32 bootloader from JWR66V. I flashed the .img file from this thread using Wugfresh's fantastic toolkit. (linked to in the 2nd post of this thread).
Click to expand...
Click to collapse
I would recommend learning how to use adb and fastboot. Toolkits do not always work as expected and you will then need to use fastboot to fix it

Can't flash twrp?

Hello guys, I tried to flash Dirty Unicorns ROM
I have a brand new nexus 6p
At first I went through this tutorial:
http://forum.xda-developers.com/nexus-6p/general/guides-how-to-guides-beginners-t3206928
First stuck was when I tried fastboot devices in cmd, those USB drivers from sdk manager didn't seem to work, so I downloaded some other driver, which seemed to work
Now I am stuck here:
How To Install A Custom Recovery On Your Device
fastboot flash recovery <filename>.img
So in my CMD I did this:
C:\SDK\android-sdk-windows\platform-tools>fastboot flash recovery twrp.img
target reported max download size of 494927872 bytes
sending 'recovery' (16932 KB)...
OKAY [ 0.579s]
writing 'recovery'...
OKAY [ 0.231s]
finished. total time: 0.827s
and after fastboot reboot, the device is still the same, still the same bootloader, when I hit "recovery mode", there is just the green android robot lying on his back with red ! and after a while the device just starts like normal
also when I start I see "your device software cant be checked for corruption. Please lock the bootloader......" etc and Google logo with unlocked lock in the bottom, but I guess it's normal
any advice please?

solved, /thread

bejek said:
solved, /thread
Click to expand...
Click to collapse
Please post how you solved your issue so it's here for someone searching for an answer in future.

well I found some other guide how to unlock, flash twrp, root etc...
in this guide there is completely missing one step, where you must download some modified boot image and flash it before flashing twrp
so after I performed this:
fastboot flash boot boot.img
I was able to flash twrp recovery...

bejek said:
well I found some other guide how to unlock, flash twrp, root etc...
in this guide there is completely missing one step, where you must download some modified boot image and flash it before flashing twrp
so after I performed this:
fastboot flash boot boot.img
I was able to flash twrp recovery...
Click to expand...
Click to collapse
You don't need a modified boot.img for TWRP unless:
A) You're running extremely old firmware
B) You've flashed an extremely old version of TWRP
C) You're running Android N
What version of TWRP did you flash? Were you previously using Android N?

Heisenberg said:
You don't need a modified boot.img for TWRP unless:
A) You're running extremely old firmware
B) You've flashed an extremely old version of TWRP
C) You're running Android N
What version of TWRP did you flash? Were you previously using Android N?
Click to expand...
Click to collapse
Hello Heisenberg,
it was a brand new Nexus 6p, just put out of the box.
I believe there was some stock Android 6.0.0 installed.
I tried to flash TWRP 3.0.2 obviously.
I still wanna thank you for your awesome guide, but without this step with flashing some modified boot.img first I really wasn't able to flash TWRP...

bejek said:
Hello Heisenberg,
it was a brand new Nexus 6p, just put out of the box.
I believe there was some stock Android 6.0.0 installed.
I tried to flash TWRP 3.0.2 obviously.
I still wanna thank you for your awesome guide, but without this step with flashing some modified boot.img first I really wasn't able to flash TWRP...
Click to expand...
Click to collapse
You did enable OEM Unlock under developer options right? That's very odd you found a guide that said to flash a modified boot.img. Can you post a link to the guide?

Jammol said:
You did enable OEM Unlock under developer options right? That's very odd you found a guide that said to flash a modified boot.img. Can you post a link to the guide?
Click to expand...
Click to collapse
Ofc I did.
I am not sure where did I see it for the first time, but this step was definitely in more guides than just this one.
for example here:
https://devs-lab.com/root-install-twrp-in-nexus-6p.html
and this is the step I am talking about:
Prerequisites:
Unlocked Nexus 6P bootloader.
ADB USB Drivers
Minimal ADB Package
TWRP Recovery: Nexus 6P.
SuperSU (For Root): Download.
Modified Boot.img: Download.
Installing TWRP Recovery in Nexus 6P:
1. Launch command.bat file & type:
fastboot flash boot boot.img

bejek said:
Hello Heisenberg,
it was a brand new Nexus 6p, just put out of the box.
I believe there was some stock Android 6.0.0 installed.
I tried to flash TWRP 3.0.2 obviously.
I still wanna thank you for your awesome guide, but without this step with flashing some modified boot.img first I really wasn't able to flash TWRP...
Click to expand...
Click to collapse
A modified boot.img hasn't been required for quite some time, and still isn't required. I can see from the link you gave that the modified boot.img is for MDB08K, which is a very old build. This means that guide, and any guide that instructs you to flash a modified boot.img, is outdated unless you're on quite an old build. What build are you actually on?

Heisenberg said:
A modified boot.img hasn't been required for quite some time, and still isn't required. I can see from the link you gave that the modified boot.img is for MDB08K, which is a very old build. This means that guide, and any guide that instructs you to flash a modified boot.img, is outdated unless you're on quite an old build. What build are you actually on?
Click to expand...
Click to collapse
Well I know it's outdated, but without it I wasn't able to flash TWRP - and trust me, I tried every guide here at XDA and went through a big bunch of threads, I was really desperate.
I have no idea what build was originally in my 6p, some 6.0.0.
Now I am on newest stock, MTC20F

bejek said:
Well I know it's outdated, but without it I wasn't able to flash TWRP - and trust me, I tried every guide here at XDA and went through a big bunch of threads, I was really desperate.
I have no idea what build was originally in my 6p, some 6.0.0.
Now I am on newest stock, MTC20F
Click to expand...
Click to collapse
You really just needed to update to the latest build before unlocking/rooting (standard procedure), then any current guide would have been fine. Either way you got it done though, so happy days.
The fact that you have no idea what build you were on previously is a little worrisome though, it's one of those basic things you should know before you start messing with your phone. But you're new to this so it's a learning curve I guess.

Instead try out,
fastboot boot twrp_src_name.img
(Where twrp_src_name is your TWRP file name)
That should directly boot you to the TWRP. Else try custom TWRP builds like the one with MultiROM.

Heisenberg said:
You really just needed to update to the latest build before unlocking/rooting (standard procedure), then any current guide would have been fine. Either way you got it done though, so happy days.
The fact that you have no idea what build you were on previously is a little worrisome though, it's one of those basic things you should know before you start messing with your phone. But you're new to this so it's a learning curve I guess.
Click to expand...
Click to collapse
Yeah, you are obviously right. I didn't even let it update to the latest stock build and went straight to flashing new rom, so I guess there was the problem with TWRP.

bejek said:
Yeah, you are obviously right. I didn't even let it update to the latest stock build and went straight to flashing new rom, so I guess there was the problem with TWRP.
Click to expand...
Click to collapse
If you don't boot into recovery right after flashing it, the standard recovery will overwrite it. If you want to prevent this, after flashing TWRP, boot directly into TWRP. Flash latest SU to root it (This will prevent the system from overwriting twrp on reboot.)