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Cannot Access Fastboot Mode lollipop (ver 5.02)

R

rockfordpi

Newbie
Help! I am trying to root. I have been Reading and Pressing Power button and Volume down for two days now and still can't get into fastboot mode. I am not an expert, but I rooted my previous M8's without issue.

I am using an an ATT version, android 5.02, with no SIM card installed (has been unlocked from ATT network). I still have not been able to get bootloader unlocked.

I can get to the recovery screen (power-volume down-power) , but when I boot to bootloader, it goes black and I have to manual restart.

Pressing Volume down/power together does nothing.

The best response I get is with Windroid Universal android kit.

When I click unlock bootloader and select the unlock code, it tells me it is flashing, then it says it is rebooting and re-enable USB debugging when rebooted, and phone powers down, but never powers back, I have to manual restart. When I do the manual restart, USB has not been disabled, so I don't think it is being unlocked.

Basically the same things happen when I try to flash TWRP and SUPERSU. If I recall correctly, the phone needs to be in Fastboot mode for this to work. Can anyone tell me if I am forgetting something or doing something wrong or otherwise give me any suggestions?
 
Do you have the adb and fastboot tools set up on your PC? If so, with phone booted normally, turn USB debugging on, connect phone to PC, open command prompt window from folder where adb.exe is, and type:

adb reboot bootloader
 
saltire said:
Do you have the adb and fastboot tools set up on your PC? If so, with phone booted normally, turn USB debugging on, connect phone to PC, open command prompt window from folder where adb.exe is, and type:

adb reboot bootloader
Click to expand...
Tried it. Phone powered down when I gave command but never came back (or at least I have a black screen)

I did notice one thing. When phone powered down, I heard the normal "USB device disconnected" sound you get when you remove a USB device. However, IMMEDIATELY after that, I got the same sound again, like I had just reconnected a USB device. Could that second sound have been my phone restarting in fastboot mode? (phone does not show up in my drive list).

Is it possible the phone did come back in fastboot mode and I am just not seeing it on screen?

However, I did adb reboot recovery and it rebooted to recovery mode and I can read all of the recovery options on screen. Of course when I chose reboot to bootloader from this screen, it restarts and leaves me with a black screen per above...
 
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It doesn't sound good, but maybe. You can try testing this, phone in fastboot (black screen), connected, from cmd prompt:

fastboot devices

and see if you get phone serial number returned. Then you could try:

fastboot getvar all

and post the info that get's returned, but scrub out your IMEI and serial number first (if the command works).

I don't know if there is a command that will return locked or unlocked status, but the above info is useful to know and should confirm if phone is going in to fastboot mode at least.

You can then do:

fastboot reboot

and see if phone reboots normally. If these work then it sounds like phone is going in to fastboot mode, but it's a concern that you can't see bootloader screen at all. (I'm assuming that you are not S-OFF.)
 
First, let me say THANK YOU FOR ALL OF YOUR HELP. I try to read and figure things out on my own, but I was at a dead end on this one.

Ok, Everything you said do works. Output pasted below. below Says S-ON. Fastboot reboot did reboot me.

I have some more questions and info about the phone, but I will hold off until you see below, that may tell you exactly what the problem is.


C:\adb>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: 3.19.0.0000
(bootloader) version-baseband: 4.0.U605611@50319A
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 4.28.502.2
(bootloader) version-misc: PVT SHIP S-ON
(bootloader) serialno: ###############
(bootloader) imei: ##################
(bootloader) imei2: Not Support
(bootloader) meid: 00000000000000
(bootloader) product: m8_ul_ca
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B12000
(bootloader) cidnum: CWS__001
(bootloader) battery-status: good
(bootloader) battery-voltage: 0mV
(bootloader) partition-layout: Generic
(bootloader) security: on
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: 7f8e91a3
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0
all: Done!
finished. total time: 0.085s
 
OK, all of that looks normal, which is good. I can't vouch for that toolkit though, and never really trust them. Did you get the unlock code via htcdev.com? We don't know if your bootloader is unlocked, but you could download latest version of TWRP and try to flash it through command prompt, with phone in bootloader.

I can't help think this is somehow related to the toolkit though, and running a full RUU could be the best bet to clean things up properly. Am out tonight but will get back to you. Meantime, I'd suggest doing a backup of your phone, copy everything from internal storage you want to keep to your PC. That's if unlocking the bootloader hasn't worked, if it did your phone will have already been wiped.
 
Nothing on this phone I need to keep, it has already factory reset about 3 times this week, LOL. I tried to flash unlock code again using Abd and got this

C:\Android>fastboot flash unlocktoken Unlock_code.bin
sending 'unlocktoken' <0 KB>...
OKAY [0.151s]
writing 'unlocktoken' ...
<bootloader> unlock token check successfully
OKAY [ 0.006s]
finished. total time: 0.158s

So, only way to really know if it is actually unlocked is to try to flash TWRP?
 
I GOT IT ROOTED! TWRP INSTALLED AND ROOTED IT.

Thanks. GREAT HELP, could not have done it without your help. Never did see fastboot on phone screen.

Any additional advice? All I really want to do is make a user app a system app and it had to be rooted for that.
 
OK, good stuff. Two things I guess. Recommend you do a full backup in TWRP to external SD card, once you're all set up, so you can restore back to working phone if need be.

I'd still think about running a full signed RUU at some point, the bootloader issue is still a slight concern.
 
Ok, understand the backup, why/how.

Not completely clear on the RUU. As I understand, it will re-image the entire phone and I am ok with that. However, I read where bootloader had to be locked, so I think I run the OEM lock from ADB?

Do I restore back to factory and then try to unlock and root again or should I try to re-image with with an image that is already unlocked and rooted? Where is a good source for the images or whatever they are called?
 
Yep, the RUU will do a complete wipe and fresh install. Correct, you would need to relock the bootloader first to run it.

Doing this is really just to resolve your unusual bootloader issue, which is firmware related. This is separate from software so there is no unlocked image with respect to the bootloader. The ROM and kernel together make up your system software, and most custom ROMs include root access via SuperSU.

If phone works fine then it's up to you if you just want to leave it as is, or try and resolve the bootloader issue. You're lucky as being on one of the US carriers you can get latest full RUU to download from here:

http://www.htc.com/us/support/rom-downloads.html

Apart from anything else, these are very useful to have as a backup just in case (you obviously want the AT&T download for 4.28.502.2 to match your version-main output from the "fastboot getvar all" command you ran earlier).
 
Couple of more questions

1. If I do the full backup to SD card via TWRP, and something goes wrong with RUU, can I still restore back to current state?

2. This phone was an ATT phone, when contract was up the sent me an unlock code to unlock from their network, which I did. When I factory reset (a couple of times), it locked back to their network, I know I can use code to unlock again, because I did

My question is, do I use the ATT RUU or the unlocked developer RUU? If I use the ATT RUU, will I be able to use the code they gave me (or other method) to unlock it from the ATT network for another carrier (tmoblile)?

The developer version, 6.12.1540.4, is android 6. Not sure if that will work or if it is something I would even want. Will this version limit my ability to customize the phone?

My main goal is to be able to install a user app as a system app.
 
1 - Yes, but you would need to Unlock the bootloader and flash TWRP recovery again, then restore your backup. Note the backup doesn't include files saved to internal storage either so you would have to back up/copy everything you wanted to keep to PC before running the RUU.

2 - You are S-ON, which is an in-built security mechanism to prevent you from installing firmware that is not for the specific phone hardware model, and carrier version - and thus turning the phone in to an expensive paperweight. So you can only run the AT&T RUU, as it checks for a match with your modelid and CID before installing anything firmware related - if they don't match then it won't run.

Regarding the unlock code I see no reason why it wouldn't work, but I've no experience with this as I'm in the UK and always get my phones from independent suppliers so they are network unlocked.

If phone is working fine as it is, then stick with it. You will have the AT&T RUU to hand if you need it.
 
Should have followed your advice and left well enough alone, but I kept worrying about that fastboot issue, so I flashed the RUU.

The good news is, the phone still seems to work. Still can' get fastboot with keys, but can using adb.

However, now when I try to flash the twrp recovery, I keep getting this error:

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flash rec
twrpm8.img
target reported max download size of 1826414592 bytes
sending 'recover' (14818 KB)...
OKAY [ 1.446s]
writing 'recover'...
(bootloader) signature checking...
FAILED (remote: signature verify fail)
finished. total time: 1.984s

I have tried TWRP 3.0 and the previous version

I flashed the unlock code. Question, do I generate a NEW unlock code AFTER flashing NEW RUU or use the old one? I think I tried it both ways. It is confusing to me because every time I run get oem token, I get a different set of numbers. Is that normal?

Below is my getvar output

version: 0.5
version-bootloader: 3.19.0.0000
version-baseband: 4.0.U605611@50319A
version-cpld: None
version-microp: None
version-main: 4.28.502.2
version-misc: PVT SHIP S-ON
serialno:
imei:
imei2: Not Support
meid: 00000000000000
product: m8_ul_ca
platform: hTCBmsm8974
modelid: 0P6B12000
cidnum: CWS__001
battery-status: good
battery-voltage: 0mV
partition-layout: Generic
security: on
build-mode: SHIP
boot-mode: FASTBOOT
commitno-bootloader: 7f8e91a3
hbootpreupdate: 11
gencheckpt: 0

tal time: 0.105s
 
So are you now able to see the bootloader screen on the phone?

I'm assuming not, as the error you are getting is because the bootloader hasn't been Unlocked successfully. You would (or will) need to get a new code as I think the RUU will have included all firmware including bootloader.
 
Still unable to see the the bootloader screen or access with keys.

Have tried to unlock with new code, did not get an error. Still will not flash

Also, immediately after I unlock with new code, it will not even attempt to flash the recovery, I have to reboot, and then try and that is when I get message above.

I do have backup made by TWRP on SD card and I can boot to stock recovery. However, I think I need more than that to b able to restore.

Why do the OEM unlock token numbers change every time I do oem get token command? That is counter intuitive to me. Seems like if those numbers are changing, then the unlock code from HTC would be changing each time as well. This question may be beyond my background to understand, if so, let it go and I will focus on getting recovery back.
 
I used Sunshine to gain S-OFF as soon as I got the phone out of the box so have never had to bother with the whole bootloader lock/unlock process, and can't advise much on that I'm afraid. I don't understand why the bootloader is persisting with a sig check if it is unlocked however - that just doesn't make sense. No the stock recovery won't do you any good, it is there to wipe when doing a factory reset and can do a clear cache as well, but that's it.

Does fastboot report the unlock being successful? If so then it might be worth doing:

fastboot erase cache

fastboot reboot-bootloader

fastboot erase cache

before trying to flash TWRP again.

I'm not aware of any AT&T specific restrictions on the bootloader, as far as I know it's only Verizon who don't allowing users to do the unlock via htcdev.com - so scratching my head a bit here I'm afraid.

Other option may be to try and run Sunshine, but it may have changed to need root first and I don't know if it still unlocks the bootloader as well - it had temp root built-in and also happened to unlocked the bootloader when I ran it in 2014.
 
Where can I find sunshine download and instructions. I am also googling it, found the ninja site but the college where I work has it blocked. Thought you might know another resource.

I think I followed your directions below:

C:\adb>fastboot erase cache
******** Did you mean to fastboot format this partition?
erasing 'cache'...
OKAY [ 0.190s]
finished. total time: 0.197s

C:\adb>fastboot reboot-bootloader
rebooting into bootloader...
OKAY [ 0.015s]
finished. total time: 0.016s

C:\adb>fastboot erase cache
< waiting for device >
******** Did you mean to fastboot format this partition?
erasing 'cache'...
OKAY [ 0.185s]
finished. total time: 0.186s

C:\adb>fastboot flash recovery twrp30m8.img
target reported max download size of 1826414592 bytes
sending 'recovery' (20022 KB)...
OKAY [ 1.808s]
writing 'recovery'...
(bootloader) signature checking...
FAILED (remote: signature verify fail)
finished. total time: 2.530s

C:\adb>
 
This still says to me that the bootloader is Locked. This might help to confirm this though:

fastboot oem device-info

and see what it says.
 
I did this from bootloader mode:

C:\adb>fastboot oem device-info
...
(bootloader) [ERR] Command error !!!
OKAY [ 0.003s]
finished. total time: 0.004s

C:\adb>
 
Yeah wasn't sure if that command would work or not - guess HTC's implementation differs slightly. Is the unlock process successful, yes? If it is try TWRP 2.8.7.0 instead of the very latest version, as it could be a bad download or something related to the new builds.

You'll only get Sunshine from the root.ninja site so you'll need to try from another location.
 
I tried the earlier version of TWRP. If I understood from your post above, there is no real way to know if the unlock was successful. However, I did not get an error message when I gave the unlock command.

I do not have SIM card in phone, I can't imagine that would matter.

Unless you have other suggestions, when I get home, I think I will unlock the phone from the ATT network and then get the OEM token and try the unlock again.
 
Ok, tried per above, did not work, but I did learn something.

I flashed ATT RUU. However, when I put in the SIM card from another carrier (T-mobile) the phone worked with that SIM card without me putting in the unlock code ATT sent me. So, it appears I have done something to the phone.

Still, when I try to flash recovery, I get

C:\Program Files (x86)\Android\android-sdk\platform-tools>fastboot flash recover
twrp30m8.img
target reported max download size of 1826414592 bytes
sending 'recover' (20022 KB)...
OKAY [ 1.884s]
writing 'recover'...
(bootloader) signature checking...
FAILED (remote: signature verify fail)
finished. total time: 2.611s
 
There was a typo in that particular run, but I get the same message when I type it correctly:

Same Results:

C:\s>fastboot flash recovery twrpm8.img
target reported max download size of 1826414592 bytes
sending 'recovery' (14818 KB)...
OKAY [ 1.438s]
writing 'recovery'...
(bootloader) signature checking...
FAILED (remote: signature verify fail)
finished. total time: 1.976s

C:\s>
C:\s>fastboot flash recovery twrp30m8
error: cannot load 'twrp30m8'

C:\s>fastboot flash recovery twrp30m8.img
target reported max download size of 1826414592 bytes
sending 'recovery' (20022 KB)...
OKAY [ 1.889s]
writing 'recovery'...
(bootloader) signature checking...
FAILED (remote: signature verify fail)
finished. total time: 2.616s

C:\s>
 
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