Database Develop

[Newbie Guide] adb/fastboot/bootloader/android 101

The purpose of this document is to clarify a few basics about HTC Android Phones and basic commands to interface with the phones. Think of this as a beginner's guides to the Android device from a non-traditional user's point of view. I'll keep it simple and plain as much as I can for the new users. I'll also try to keep all the technical aspects true as much as I can while keeping it simple.
Before you go on, please read this and understand the basic concepts and how and why following commands are being used. Do not follow anyone's instructions/tutorials/guides without prior basic understanding of what each command do. I do want to believe it's humans visiting this forum and not lemmings. If you do not understand, feel free to ask here. I will or someone else also knowledgeable will answer your questions. DO NOT QUOTE THIS AS A WHOLE. My pet peeves and a complete waste of screen space.
Sometime, depending on your OS, command names may change (e.g: mouse / mouse.exe / mouse-linux / mouse-mac). For general purpose, we'll use mouse instead of an OS specific commands in this instructions.
So to repeat myself, if you understood the concepts of the commands, and you are on a linux system and someone's guide says touch index.php, you will automatically type touch-linux or whatever the name of your executable is on your system.
​
We shall assume you know how to install needed drivers and where to get android sdk and put the sdk binaries (executables) in the system path. If we need to expend this let me know and I'll expend this here.
Further, if I get any parts wrong, PM me and I'll get those parts corrected.
Android Partition, SPL etc.
Partitions:
Followings are a list of partitions on your android phone.
misc - misc partition -
recovery - Recovery Partition - This is where the original HTC recovery or Amon Ra's recovery or any other Recovery would go. Basically if you reboot into recovery it'll boot from here.
boot - This is your boot partition
system - This is where all your system information (ROM resides)
cache - cache (When you factory reset the phone, this area is wiped)
userdata - user data (like your login, your user settings etc) When you factory reset the phone, this area is wiped)
So, if you replace the recovery image, you are pretty much set for updates provided here at XDA. Note: By replacing your recovery image, you may not be able to have OTA updates.
ROM images will normally replace boot and system images at the same time and often time, userdata and cache too; reseting the phone completely.
SPL/Bootloader/Radio/Bricking Phones:
SPL / Bootloader is like BIOS on a computer. At least I think of it that way. SPL can be updated! SPL comes as either Security-On of Security-Off (S-ON/S-OFF).
Note: It is my understanding that radio will boot first, followed by other systems. So it is IMPORTANT that your radio image/version will work with your SPL image/version. This is the one and only reason for phones being bricked. You can not brick your phone by flashing a ROM or Boot image or recovery image. Once you flash the wrong radio for the SPL, the only known method of recovery is to send the phone back into HTC for repair.
How do I know the phone is bricked? A bricked phone can not boot into bootloader, recovery, or into normal operation modes. You can not connect to a bricked phone via adb or fastboot. You can only see one screen on the phone and it will be the first splash screen.
Commands:
adb - Android Debug Bridge - One of the two things you'll need to know if you ever want to do anything non-conventional on your android based phone.
List of commands that can be used by adb can be prompted by typing adb at the system shell (command prompt or terminal)
Notable adb commands:
adb devices - If you don't know anything, this is the ONE thing you have to know.
adb devices will give you a list of devices connected to the computer. This is also a good way to make sure that your phone is actually connected to the computer.
adb reboot (bootloader|recovery)
adb reboot - this will reboot your phone normally.
adb reboot bootloader - this will reboot your phone back into the bootloader (white screen with the android on wheels)
adb reboot recovery - this will reboot your phone back into recovery console (either default or amon_ra's recovery).
adb shell - this will shell into the phone and you can now explore the phone. Remember phone's native backend os is linux so know your linux commands.
adb remount - remounts the system partition on the phone so you can you read/write to it.
adb push xxx yyy - will push xxx file from computer into yyy location/file on phone (needs rooted access)
adb pull xxx yyy - will pull xxx file from phone into yyy location/file on computer (needs rooted access)
Fastboot is protocol used to update the flash filesystem in Android devices from a host over USB. It allows flashing of unsigned partition images.
Notable fastboot commands:
fastboot devices - If you don't know anything, this is the ONE thing you have to know.
fastboot devices will give you a list of devices connected to the computer. This is also a good way to make sure that your phone is actually connected to the computer.
fastboot reboot - this will reboot your phone normally
fastboot oem unlock - this will unlock your bootloader - NOTE THIS WILL VOID YOUR NEXUS ONE WARRANTY
fastboot erase XXX - Will erase the partition XXX (such as userdata, cache) - mainly used for resetting phone and clearing userdata / factory settings.
fastboot flash XXX YYY - This will flash XXX partitionn with YYY image.
e.g: fastboot flash system system_update.img will flash/update your system partition with an image called system_update
If anyone needs me to dig deep into using anything else, please PM me. I'll add it on here. Hopefully this will help all newbies about the basic commands and what they do.
FAQs (UPDATED Feb 09, 2010)
Q: One question about the Android SDK. Do I need it to flash my N1 or just to program new apps? Where can I get it?
A: Android SDK is not entirely needed to flash the N1. However, there are tools in there that you need. Adb / Fastboot etc. Although they can be downloaded by themselves, the windows version of the SDK also have the Drivers that are needed for android devices for USB connection. So, it is recommended to get it. You can get it from developer.android.com
Q:I have never experienced anything like this when I did a hard-spl on my winmo phone. Radio versions are included with SPL's, right?
A: Official packages from HTC did come with nbh packaging, meaning it is a all in one upgrader that will update Radio, ROM, System etc, it is very much common for active development area here at XDA to get the radio or SPL or ROM separately and independently of one another. And as such, you will most likely flash them seperately (who wants to wait 6-8 months). Also, since this phone is released by google, HTC will most likely not update any major Radios. However, it is very likely that we will be hacking in Radio updates or any other "updates" from HTC from their new device - HTC Bravo.
Q: Is there a guide for snow leopard? I'm kind of stuck.
A: I personally ran android SDK and aforementioned executable on both MAC OS 10.5 and 10.6. Like I posted, the commands and the executable names may be slightly different. I may call adb and you may find it as adb-mac. I am not going to write 3 separate documents for 3 separate OSes. You have to know that adb=adb-mac (on your mac), adb-linux (for linux) etc. And yes the above guide will work universally.
Q: Can i replace the splash image..?? (unlocking related)
A: As of the above date (next to the FAQ) no you can not. Issue is probably a few folds. One of them is that splash1.img is not going in due to security lock. Remember, you unlocked the phone. HTC will not like it. Anyhow, I like the current quad color X. If you are thinking of getting rid of the lock logo, good luck. Even if you can get rid of it, you will still have to overcome the pink text that says ***UNLOCKED*** on your bootloader.
Q: Can you run Windows Mobile on Android Phones?
A: With enough resources given, sure. Will it ever happen? No. Why? Windows mobile compiler and builder cost $. As a matter of fact, as of version 5, it was going to cost me $75 per device. That's one of the reasons why handset makers went to Android open platform. Android is free and universal so as long as you use certain chipsets and certain items, you are good to go. Can it ever be ported? Sure. With right amount of time and money anything can be done. But at this point, it's cheaper for you to go buy a windows mobile smartphone.
Q: How do I know the phone is bricked?
A: You can not brick a phone unless you are flashing Radio/SPL packages. Make sure if you are doing that, you follow directions VERY CAREFULLY. A bricked phone can not boot into bootloader, recovery, or into normal operation modes. You can not connect to a bricked phone via adb or fastboot. You can only see one screen on the phone and it will be the first splash screen.
Q: I have installed the Android SDK however, i cannot seem to get the laptop to detect the nexus. What have i left out?
A: Most common item that people forget to enable is USB Debugging. Settings => Applications => Development => USB debugging [checked]
Q: I have rooted n1. when I go to recovery to do backup, I get the triangle with the little green android guy, but phone is stuck there. I have to remove battery to reboot phone. What have I done wrong?
A: You still have the stock (shipping) recovery. If you want a different recovery (Amon RA's), download it, the from fastboot, run fastboot flash recovery downloaded_recovery.img
Q: Which step of the rooting / recovery procedure does it give root?
A: Root and Recovery are two totally different things. Recovery is a partition that contain recovery information. Stock recovery is what allows OTA updates etc. Normally it will search for update.zip in the root folder of the SD card. Amon_RA's Recovery or any other recovery images are there to enhance the traditional stock recovery. Amon Ra's Recovery for example, contains thing such as ability to update from different zip files, and backup/restore of your data/system.
Rooting is not done by recovery but is a kernel level access (simply put) that will give root or "SU". It is done by patching the boot partition of the your android device.
Q: What are the differences, advantages, disadvantages of the different ROM's?
A: They are all different. Some have some features, some are plain stock, some are made for bleeding edge kernel etc. You'll have to try them out and figure out yourself. I may make a chart of what they are (see the bottom at my signature - wiki) but with too many android devices, I will need some major help. One person alone will not have total knowledge of all the ROM releases. There are just way too many devices and ROMs.
Q: Which ROM will allow OTA updates?
A: Stock ROM WITH Stock Recovery.
Q: If the phone is SIM/carrier unlocked and you root do you have to SIM unlock again?
A: SIM/Carrier unlock has nothing to do with rooting your phone. You can still have root and still be carrier locked. Nexus One comes carrier unlocked from factory.
Q: How much space is there for apps? is using the sd card really necessary? (on Nexus One)
A: Search google? The phone has 512MB or space. That SHOULD be more than enough for you. If not, you have some serious issues. I do not believe you will not App2SD for Nexus One. Google did say during the release conference that they will update Android/N1 so that apps can be run/installed to SD but that requires some system and security changes (mainly to prevent pirated software - Yes if I write something, I deserve to get paid for it).
Q: When you do "flash zip from sdcard" or "fastboot flash image" does this merge and overwrite the files in to the partition?
A: When you update a software (via recovery), software my be merged. However, if you fastboot flash, just like the word flash says, it will flash and overwrite the partition.
Q: Which partition does "flash zip from sdcard" affect?
A: Depends on what you are flashing. It could be any or all of the partitions such as SPL, Boot, System, Recovery, Radio. You should study first before randomly flashing things.

sorry, got it!

blakestimac said:
i apologize if this is the wrong place for this but, but i have adb setup perfectly, but fastboot is not recognized at all. could i have missed something?
Click to expand...
Click to collapse
I need your system info.
What os are you running? where did you get fastboot? what are you trying to do?

Don't forget fastboot boot for testing images. My most used command

I still have no idea how to use or setup adb i have downloaded the sdk and used fastboot and superboot to root my phone and am currently running the cm 5.0 beta 2 rom and want to learn how to use adb so i can enable the ram. Thanks, Joe

really a noob question here.....it wa easier with Hero.
i have installed the Android SDK
however, i cannot seem to get the laptop to detect the nexus.
what have i left out?

wishmaker738 said:
really a noob question here.....it wa easier with Hero.
i have installed the Android SDK
however, i cannot seem to get the laptop to detect the nexus.
what have i left out?
Click to expand...
Click to collapse
Check the FAQ.

dylanfan424 said:
I still have no idea how to use or setup adb i have downloaded the sdk and used fastboot and superboot to root my phone and am currently running the cm 5.0 beta 2 rom and want to learn how to use adb so i can enable the ram. Thanks, Joe
Click to expand...
Click to collapse
Ok. I need to know what you actually did. I am not understanding what you are trying to do.

Can't run adb commands - device not found
Thanks for the info. I am having an issue with running adb commands. My phone is rooted via superboot and I tested it with Nexus Torch which works. Now I am trying to install the new kernel so I can run the wireless tether app... but I can't get any of the adb commands to recognize the phone. I boot the phone by holding the trackball and power button. I am in USB debugging mode. When I run fastboot devices, the phone serial number shows up. When I run adb devices, it says no device detected. And when I try to run any other adb commands they do not work, even though fastboot commands work. Any ideas? Thanks.

Sorry i was pretty vague before i down loaded the sdk and also installed the adb setup file included with the superboot pack but just have no idea how to get it to work and add things through adb. I tried typing adb commands into comand line with the phone connected to the computer but nothing happend. just said not recognised command so i just basically need a rundown of how to setup adb.

dylanfan424 said:
Sorry i was pretty vague before i down loaded the sdk and also installed the adb setup file included with the superboot pack but just have no idea how to get it to work and add things through adb. I tried typing adb commands into comand line with the phone connected to the computer but nothing happend. just said not recognised command so i just basically need a rundown of how to setup adb.
Click to expand...
Click to collapse
I'm a noob so can't offer much help...but I would make sure the usb drivers are installed if you're using windows....this probably should have happened when you installed the sdk, but you can also install it through the device manager and point it to the folder where the usb drivers are located. Also make sure the phone is in USB debugging mode. also you may need to reboot your pc. Make sure you have setup running when you run the adb commands. you need to be in the same directory as the adb file, or in the case of the superboot pack you need to type "adb-windows" not just "adb". you may also need to put .exe, ie adb-windows.exe.

pwnvds said:
Thanks for the info. I am having an issue with running adb commands. My phone is rooted via superboot and I tested it with Nexus Torch which works. Now I am trying to install the new kernel so I can run the wireless tether app... but I can't get any of the adb commands to recognize the phone. I boot the phone by holding the trackball and power button. I am in USB debugging mode. When I run fastboot devices, the phone serial number shows up. When I run adb devices, it says no device detected. And when I try to run any other adb commands they do not work, even though fastboot commands work. Any ideas? Thanks.
Click to expand...
Click to collapse
You run fastboot from the white screen. Android on non-white screen. It's one or the other. It's ADB or Fastboot (depending on the mode of the phone).

dylanfan424 said:
Sorry i was pretty vague before i down loaded the sdk and also installed the adb setup file included with the superboot pack but just have no idea how to get it to work and add things through adb. I tried typing adb commands into comand line with the phone connected to the computer but nothing happend. just said not recognised command so i just basically need a rundown of how to setup adb.
Click to expand...
Click to collapse
Is the directory where ADB/fastboot (SDK) is installled in your system path?
I am guessing it's not. If it was, just by typing adb alone (without commands), it'll give you a list of commands. Click here if you want to know how to change your system path to include a particular folder.
We're now in the age of nintendo pilots and point and click OS that no one knows how to use command lines and system paths anymore.

recovery
I have rooted n1. when I go to recovery to do backup, I get the triangle with the little green android guy, but phone is stuck there. I have to remove battery to reboot phone. What have I done wrong?

umplarry said:
I have rooted n1. when I go to recovery to do backup, I get the triangle with the little green android guy, but phone is stuck there. I have to remove battery to reboot phone. What have I done wrong?
Click to expand...
Click to collapse
Answered in FAQ area.

seraph1024 said:
Answered in FAQ area.
Click to expand...
Click to collapse
I tried that before I posted. I searched the FAQ again. Maybe I am a complete DA, but still can't find answer. I don't mind searching, it will help me to learn, but could you point me in the right direction in FAQ?

umplarry said:
I tried that before I posted. I searched the FAQ again. Maybe I am a complete DA, but still can't find answer. I don't mind searching, it will help me to learn, but could you point me in the right direction in FAQ?
Click to expand...
Click to collapse
Q: I have rooted n1. when I go to recovery to do backup, I get the triangle with the little green android guy, but phone is stuck there. I have to remove battery to reboot phone. What have I done wrong?
A: You still have the stock (shipping) recovery. If you want a different recovery (Amon RA's), download it, the from fastboot, run fastboot flash recovery downloaded_recovery.img
Click to expand...
Click to collapse
There you go.

seraph1024 said:
There you go.
[/B]
Click to expand...
Click to collapse
Thanks for your help

seraph1024 said:
There you go.
[/B]
Click to expand...
Click to collapse
I had it downloaded, just had not flashed it

I've been looking all over, but I probably need to check the HTC Dream forum or something.
How do I install a custom ROM? I know you have to adb push update.zip somewhere, but I can't find any info about this. Please help.

phone doesn't boot (can only get to fastboot USB menu)

i can only access the white screen when i chose bootloader>recovery i get the /!\ sign.
i installed the USB driver and i was able to use only the "fastboot" commends. adb commend didn't work. when i type fastboot devices i get the serial no. of the device.
when i use the adb devices commend i get: "List of devices attached" and an empty line.
is it possible to fix this phone? thanx in advance.

Asilns said:
i can only access the white screen when i chose bootloader>recovery i get the /!\ sign.
i installed the USB driver and i was able to use only the "fastboot" commends. adb commend didn't work. when i type fastboot devices i get the serial no. of the device.
when i use the adb devices commend i get: "List of devices attached" and an empty line.
is it possible to fix this phone? thanx in advance.
Click to expand...
Click to collapse
adb only works within android since it's a debugger if I'm not mistaken. Try using fastboot to flash the system images of the stock rom back to their respective partitions. (ie. fastboot flash system system.img; fastboot flash boot boot.img; etc.)
You must be unlocked for that to work however.

problem solved
after almost 10 hours of research the solution was really easy.
1.download "recovery-RA-nexus-v1.6.2.img" and fastboot it using this commend:
fastboot-windows flash recovery recovery-RA-nexus-v1.6.2.img
2.flash a rom from SD card and everything should work fine

[Q] Can't get past Recovery Mode - Need Help!

After rebooting for a cyanogenmod update which failed to install, my phone will not boot into Cyanogenmod - only clockwork.
I have precious data on the phone that I need to extract, mainly pictures.
ADB only recognizes the phone as "offline" and I cannot pull any files from it.
Any suggestions? Thanks a lot guys.

icer22x said:
After rebooting for a cyanogenmod update which failed to install, my phone will not boot into Cyanogenmod - only clockwork.
I have precious data on the phone that I need to extract, mainly pictures.
ADB only recognizes the phone as "offline" and I cannot pull any files from it.
Any suggestions? Thanks a lot guys.
Click to expand...
Click to collapse
did you cleared cache?
When you are trying to use adb your phone is in cwm recovery?

alray said:
did you cleared cache?
When you are trying to use adb your phone is in cwm recovery?
Click to expand...
Click to collapse
Yes I've cleared the cache and rebooted with the same results - just boots back into Recovery Mode.
And yes, when I am using ADB I am in Recovery Mode. I can't get past that.

icer22x said:
Yes I've cleared the cache and rebooted with the same results - just boots back into Recovery Mode.
And yes, when I am using ADB I am in Recovery Mode. I can't get past that.
Click to expand...
Click to collapse
Do you have a nandroid backup on your phone?
Also is all your drivers properly set and updated on your cumputer? Can you post a screenshot of Windows devices manager with the phone info?
Are you using the original usb cable? Some usb cables only have GND and 5V pins (no data). Also be sure to use usb 2.0 and a usb port directly from your motherboard (not in front of your computer) and don't use any usb hub.

Well I got it recognized by ADB now.
What is the file structure like in order to pull files from the phone?
What commands can I use in ADB to pull the main sd directory?

icer22x said:
Yes I've cleared the cache and rebooted with the same results - just boots back into Recovery Mode.
And yes, when I am using ADB I am in Recovery Mode. I can't get past that.
Click to expand...
Click to collapse
oh and when you are in bootloader, is fastboot working?
Code:
fastboot devices
does it says fastboot usb or only fastboot (in red)
I nerver used adb to pull files so idk. Maybe somthing like ''adb pull /sdcard/ C:\something'' ?
maybe you can find here
or use twrp to make a backup of your data, then pull the backup to your computer

alray said:
oh and when you are in bootloader, is fastboot working?
Code:
fastboot devices
does it says fastboot usb or only fastboot (in red)
I nerver used adb to pull files so idk. Maybe somthing like ''adb pull /sdcard/ C:\something'' ?
Click to expand...
Click to collapse
Thanks man. That helped.
If anyone ever finds themselves in this situation, make sure your SDK packages are updated to the latest Android OS version. This is why ADB was recognizing my device as offline.
Also, running the command adb pull /sdcard/ C:<somewhereonyourPC> will pull all the data from your HTC one.

icer22x said:
Thanks man. That helped.
If anyone ever finds themselves in this situation, make sure your SDK packages are updated to the latest Android OS version. This is why ADB was recognizing my device as offline.
Also, running the command adb pull /sdcard/ C:<somewhereonyourPC> will pull all the data from your HTC one.
Click to expand...
Click to collapse
oh nice to see adb pull /sdcard/ C:<somewhereonyourPC> was the right syntax :laugh:
For the sdk packages you should always make sure it is updated before doing anything to the phone. Same for drivers. An ''adb devices'' and ''fastboot devices'' won't hurt before messing with the phone to make sure everything set correctly.
Now I presume you'll be ok to flash your rom again?1

System partition deleted, need help.

Evening all. I've done a very dumb thing. While wiping my device for a clean install in TWRP, I foolishly checked the "system" partition and wiped everything out.
Currently I have ADB set up correctly on my Mac, TWRP running on my phone but I'm stumped because I haven't used ADB in quite some time.
Can anyone help me with instructions (or a link to them) on how to restore my phone to it's former glory?

I should also tell you that I've tried following the instructions found with the Google Factory Images, but I'm unable to flash anything. I get "permission denied" messages. I'm thinking this is because I have no ROM and therefore no settings to allow me access to developer settings.
The bootloader is unlocked... but I'm stuck.

If you have TWRP, enter it. Connect your N6 to your Mac. Copy a custom ROM or one of the stock ROM flashable zips to internal storage, then install it using TWRP.
ADB isn't necessary.

What I'm doing and seeing...
I start the phone in the bootloader and plug it in. The phone sees that it's plugged in.
If I "adb devices" now, I get no results.
If I start TWRP and enter "adb devices", I see a serial and the word "recovery"
I can reboot the bootloader via adb, but that's it.
If I enter any action after that, like: "fastboot flashing unlock", or "flash-all", it returns < waiting for any device >, or permission denied.

Strephon Alkhalikoi said:
If you have TWRP, enter it. Connect your N6 to your Mac.
Click to expand...
Click to collapse
Thought about that earlier, of course. My phone isn't connecting to my Mac. I'm not seeing it as a drive in Finder.

nathanotis said:
My phone isn't connecting to my Mac.
Click to expand...
Click to collapse
I uninstalled and reinstalled android file manager. I'm pulling down a new rom, now. Fingers crossed.

That was easy...

nathanotis said:
What I'm doing and seeing...
I start the phone in the bootloader and plug it in. The phone sees that it's plugged in.
If I "adb devices" now, I get no results.
If I start TWRP and enter "adb devices", I see a serial and the word "recovery"
I can reboot the bootloader via adb, but that's it.
If I enter any action after that, like: "fastboot flashing unlock", or "flash-all", it returns < waiting for any device >, or permission denied.
Click to expand...
Click to collapse
In twrp Fastboot commands not work. And in bootloader adb commands not wotk

@nathanotis: It's for situations like this that I always store a copy of the ROM I use in internal storage. Perhaps you should do the same.

Strephon Alkhalikoi said:
Perhaps you should do the same.
Click to expand...
Click to collapse
Solid advice. Thank you.

If that ever happens again, you can always use NRT. I did that one time and used WUG's to flash a factory image and start over

OnePlus3t bricked can only boot into fastboot, however my ADB driver no longer works

I have ran into a bit of an odd problem due to me messing up a root and then messing my phone up even more while trying to fix it.
my phone is fully bricked and only boots into fastboot mode. i tried to fix it with the one-plus fixer (idk its official name) but i got an error 7. I now need to re flash an older version of TWRP and try a diffrent method but i cant as my phone no longer is recognized in fastboot using the ADB tool. I have the USB driver installed on Windows. On Linux i ran the .sh script as root and it still doesn't work.
I have both Ubuntu and Windows installed on my PC so i can do whatever you suggest me to do regardless of the os.
Thank you to anyone that can help in advanced
Malte

This is not a hardbrick; a hard one wouldn't boot at all and give no sign of life (except when plugged to PC).
Try an unbrick tool to revert to official OOS. On Windows 7+ remember to disable signed driver enforcement.

You mention fastboot and adb. Which one are you using?
Just to make sure: While in the bootloader (fastboot mode), adb does not work. You have to use the fastboot commands. Installing TWRP would be:
Code:
fastboot flash recovery <name-of-img-file>
If that's what you're already trying, just ignore this post.

I want to be able to do that but if i do adb devices it no longer finds my phone
Didgeridoohan said:
You mention fastboot and adb. Which one are you using?
Just to make sure: While in the bootloader (fastboot mode), adb does not work. You have to use the fastboot commands. Installing TWRP would be:
Code:
fastboot flash recovery <name-of-img-file>
If that's what you're already trying, just ignore this post.
Click to expand...
Click to collapse
I want to be able to do that but if i do "adb devices" in the cmd/terminal it no longer finds my phone. so my goal is to be able to execute that command. However, i may be mistaken that it doesnt need to find my phone i can just execute that command

Ive done this but it didnt fix my phone.
przemcio510 said:
This is not a hardbrick; a hard one wouldn't boot at all and give no sign of life (except when plugged to PC).
Try an unbrick tool to revert to official OOS. On Windows 7+ remember to disable signed driver enforcement.
Click to expand...
Click to collapse
I did this last night but it never fixed my phone. it boots and then says "md5 checksum error" so im needing to try a diffrent approach but i cant because i cant flash anything onto it due to adb not finding my device now

Bandella said:
I want to be able to do that but if i do "adb devices" in the cmd/terminal it no longer finds my phone. so my goal is to be able to execute that command. However, i may be mistaken that it doesnt need to find my phone i can just execute that command
Click to expand...
Click to collapse
Like I said, the adb commands won't work while in the booloader (that's why it's called fastboot mode). You need to use fastboot commands... The equivalent command would be:
Code:
fastboot devices

Bandella said:
I did this last night but it never fixed my phone. it boots and then says "md5 checksum error" so im needing to try a diffrent approach but i cant because i cant flash anything onto it due to adb not finding my device now
Click to expand...
Click to collapse
I had the same issues with md5, all you have to do is try a different USB port. I suggest the ones on your motherboard if you're on a PC. Then run the tool as administrator. I hope this helps, good luck!
P.S if it still doesn't work, try a different PC, I'm 100% sure it'll work

Bandella said:
I want to be able to do that but if i do "adb devices" in the cmd/terminal it no longer finds my phone. so my goal is to be able to execute that command. However, i may be mistaken that it doesnt need to find my phone i can just execute that command
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Click to collapse
As Didgeridoohan touched upon, adb and fastboot (while related) are different. They have different requirements and applications.
adb won't work while the device is in fastboot mode. Conversely, when the device is able to use adb, fastboot commands won't work.
adb: only works booted to OS or alternately in TWRP. Debugging must be enabled
fastboot: only works in bootloader-fastboot mode. Debugging is not required to be enabled.
For flashing TWRP, it's fastboot that you need. Well, there is a way to do it with adb, but fastboot is by far the more common way.
When in fastboot mode, adb command won't work, and there fore it is completely expected that "adb devices" yields not response. Try "fastboot devices" (no quotes) and if you get the phone's ID in response, you are in business.

Bandella said:
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my phone ... only boots into fastboot mode...
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I've had this happen to me when I've triggered dm-verity. Instead of getting the dm-verity warning display the phone would simply boot straight back to fastboot.
My solution was to:
- flash the latest TWRP using
Code:
fastboot flash recovery <recovery file. img>
- reboot into recovery (use the volume keys on the phone to select recovery and then press the power key)
-flash the full stock image I was using before the problem started
This would clean up any changes made to the boot and system images and allow me to boot the system normally.
Note: because this leaves you with a stock kernel you'll end up with the stock recovery after you boot the system.
Sent from my OnePlus3T using XDA Labs

boot your PC into Ubuntu and install adb/fastboot (tons of guides available off the 'net). then boot your 3t to dl mode and connect it to your PC. as mentioned already "fastboot devices" should list your 3t and you should now be able to flash to your heart's content. no need for drivers, unlike under Windows. i have a bootable linux usb drive primarily for this reason. curious what script you're trying to run though..