Develop Reference

Android ADB: Device unauthorized trying to connect to a port-forwarded remote emulator

Background:
I recently upgraded to an AMD processor and found that the Android device emulator was complaining about not having hardware acceleration. (This is an issue for another question). My old Intel computer worked fine, so I decided to run the emulator on the old Intel PC (emu-pc) and use my new AMD computer (dev-pc) to code.
Problem:
I wasn't able to directly have the emulator expose its ports on the emu-pc to connect to via adb on the dev-pc (again an issue for another question), so I installed the Windows 10 OpenSSH server (Microsoft instructions) and connected to it from my dev-pc, forwarding the proper ADB ports:
ssh {you}#<{remote ip} -L 5554:localhost:5554 -L 5555:localhost:5555
I then tried connecting to the remote emulator via adb:
adb connect localhost
I was met with
$ ./adb devices
List of devices attached
localhost:5555 unauthorized
I've tried a few of the posts stating you should disable and re-enable USB debugging or revoke all the USB debugging authorization or use the "Wipe Data" option in the AVD Manager. None of these worked. I also tried messing with the adbkeys on the emulator under /data/misc/adb/adbkeys but I get permission denied trying to do anything to that file. (I also can't ls it via an adb shell)
Any ideas?

I found something that worked for me. I was able to telnet to the emu-pc via port 5554, where I tried to auth on the Android console. The login message said:
Android Console: type 'auth <auth_token>' to authenticate
Android Console: you can find your <auth_token> in
'C:\Users\exile57\.emulator_console_auth_token'
I found that file and was able to log in. This made me think that the emulator thinks the connection is coming from the emu-pc, yet the keys that I was using were generated on the dev-pc. I found the keys on emu-pc in C:\Users\[your user]\.android as adbkey and adbkey.pub. I copied those to the dev-pc, killed the adb server, disconnected all devices, then tried reconnecting:
$ ./adb disconnect
./adb kill-server
./adb connect localhost
After a bit, I was able to connect and drive the device over adb:
$ ./adb devices
List of devices attached
localhost:5555 device
NOTE I'm not sure this is the whole story, as when testing this out for this answer, I deleted the dev-pc's adbkey and adbkey,pub and was still able to reconnect, so that seems a bit strange. It worked for me, but be aware, I'm not sure the mechanism.

In Android studio, Run menu > Run shows OFFLINE ... for the connected device.
Below is the procedure followed to solve it:
(Read the below note first) Delete the ~/.android/adbkey (or, rename to ~/.android/adbkey2, this is even better incase you want it back for some reason)
Note: I happened to do this step, but it didn't solve the problem, after doing all the below steps it worked, so unsure if this step is required.
Run locate platform-tools/adb
Note: use the path that comes from here in below commands
Kill adb server:
sudo ~/Android/Sdk/platform-tools/adb kill-server
You will get a Allow accept.. message popup on your device. Accept it. This is important, which solves the problem.
Start adb server:
sudo ~/Android/Sdk/platform-tools/adb start-server
In Android studio, do Run menu > Run again
It will show something like Samsung ... (your phone manufacture name).
Also installs the apk on device correctly this time without error.
Hope that helps.

Here is how I did it:
First you need to run the emulator on the host computer. I used Android Studio and I had to close it because I noticed that the adb process kept spawning.
Start port-forwarding using SSH in the development computer.
ssh -L 5554:localhost:5554 -L 5555:localhost:5555 user#emulator-host-ip
copy adbkey and adbkey.pub files found at: C:\Users\[your user]\.android from the host computer to the development computer. this step should get ride of the unauthorized problem
in the development computer kill the adb server and lookup connected devices:
$ ./adb kill-server
$ ./adb devices
List of devices attached
localhost:5555 device

React native error in launching app with android emulator

I get following error when I run react-native run-android in CMD(windows command prompt)
Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment:
https://facebook.github.io/react-native/docs/android-setup.html
What caused This problem?
Thanks in Advance.

check your device connected or not by execute below command in cmd
adb devices
if adb not found then open below dir
C:\Users\MANGO\AppData\Local\Android\sdk\platform-tools
then check device connected or not
then you can lunch your app
i hope it solve your problem

Set the sdk platform tools path in system variable inside Enviroment variable.
With this you can check the connected devices from command promt.
Note: Make sure you have connected your device to PC with USB debugging On from developer menu. You can follow this link
Then follow following steps.
From command prompt type " adb devices ", if you are connecting the real android device first time then inside your device there will be a RSA key generated which you have to click "OK".
Then to confirm from devices you can again type adb devices if all went good it will show your device.
Move to your project folder from command prompt and then run your app from command prompt.

E: Signature verification failed on Sideload

I went into the cyanogen recover menu and did a full factory reset before upgrading to LinageOS. Now when I try to sideload a package to the phone is shows "E: Signature Verification Failed"
Also, when I type
adb devices
I get back
List of devices attached
1a1e7719 unauthorized
Any help please! There is no OS to boot to so I cannot enable/disable USB Debugging etc.
Also, when I try to adb push I get the following
error: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.

List of devices attached
1a1e7719 unauthorized
This means the rsa fingerprint on your computer and the device didn't authorize the computer. This is adb failure.
In Developer Options > USB Debugging > Revoke Permissions
Turn off USB Debugging
Install ADB/Fastboot properly Full article here
Windows:
Re install adb/fastboot [Download here][2]
Ensure your device drivers are recognized by the computer. Else
download accordingly
Connect the device to computer and turn on USB Debugging.
You should some message which asks you permission to authorize and it is advisable to click on "Allow always"
adb devices
Ubuntu:
Open terminal and type sudo su
adb kill-server
adb devices
If you're able to see your device code with a name, Et Voila.
16-10-14-04

You find linageOS community help on reddit or help with Report bugs, find info here: https://wiki.lineageos.org/
I think you can copy the current linage os on the sd card and fresh install it from the recovery (TWRP)? which device do you use?
And disable zip verification in TWRP...
I use Motorola XT910, called umts_spyder.

Android ADB devices unauthorized

Configuration:
Windows 8.1
ADB version: 1.0.32
Smartphone: Oneplus One
Problem
I installed the Samsung drivers as it is said to do. When I run the ADB devices command, it said unauthorized.
Already tried:
I've done everything that'd been said on this post: https://stackoverflow.com/a/25546300/1848376
But the problem is that I don't get a prompt on the phone to tell me I must accept the connection.
When I run the command adb shell, here is the answer:
error: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.
I did "adb kill-server", but it didn't change anything. Why?

Try Revoke USB DEBUGGING Authorization.
Enable USB debugging again.
It worked.

Thankgod xda developers exist : http://forum.xda-developers.com/verizon-lg-g3/help/unable-to-access-adb-t2830087
Just had to delete adbkey file in C:Users/$Name/.android adbkey.pub was missing.
Restart after this and both files are there.
If this does not work :
- Try Revoke USB DEBUGGING Authorization.
- Enable USB debugging again.

In sequence:
adb kill-server
in your DEVICE SETUP, go to developer-options end disable usb-debugging
press REVOKE USB debugging authorizations, click OK
enable usb-debugging
adb start-server

I removed the following files from the ~/.android folder:
adbkey
adbkey.pub
I disabled and enabled ADB within device and now it works...

in Developer options,
Enable USB debugging.
Give a authorization.
(if there is no a Developer option menu, you have to click 3 times build number of Phone State menu to be developer. you can sse a developer option menu.)

Delete existing adbkeys
OR
Rename adbkeys
Best practise is to rename the keys because it provides backup.
cd ~/.Android
mv adbkey adbkey2
mv adbkey.pub adbkey.pub2
Next stop & start the server
cd ~/Android/Sdk/platform-tools
Locate the device
/Android/Sdk/platform-tools$ ./adb devices
/Android/Sdk/platform-tools$ ./adb kill-server
/Android/Sdk/platform-tools$ ./adb start-server
Then, stop the emulator Open AVD manager, click on the down arrow, then click on wipe data
Restart the emulator. Then everything works fine :)

This worked for me
1- Go to ~/.android/ and remove “adbkey”
2- Disconnect USB connection
3- adb kill-server
4- Revoke USB debugging authorizations (in developer option)
5- Reconnect the device to the Ma
6- adb devices

Try this uncheck the "verify apps via USB" in developer options and then turn on and off the "USB Debugging". It works with me.

Ensure that you have accepted the pressed the "ok" button when it is asking it is showing the fingerprint of the device after connecting through usb to your PC.

In Android studio, Run menu > Run shows OFFLINE ... for the connected device.
Below is the procedure followed to solve it:
(Read the below note first) Delete the ~/.android/adbkey (or, rename to ~/.android/adbkey2, this is even better incase you want it back for some reason)
Note: I happened to do this step, but it didn't solve the problem, after doing all the below steps it worked, so unsure if this step is required.
Run locate platform-tools/adb
Note: use the path that comes from here in below commands
Kill adb server:
sudo ~/Android/Sdk/platform-tools/adb kill-server
You will get a Allow accept.. message popup on your device. Accept it. This is important, which solves the problem.
Start adb server:
sudo ~/Android/Sdk/platform-tools/adb start-server
In Android studio, do Run menu > Run again
It will show something like Samsung ... (your phone manufacture name).
Also installs the apk on device correctly this time without error.
Hope that helps.

None of the methods listed on this page worked for me; specifically:
I had an issue where the Settings app would crash when selecting Revoke USB debugging authorizations
I was running LineageOS 14 x86_64
I was using ADB over network
The /data/misc/adb contained no adb_keys file
Removing my local ~/.android/adbkey did not help either
I had root access from the local terminal
I was not getting any confirmation dialog
adb: error: failed to get feature set: device unauthorized.
This adb server's $ADB_VENDOR_KEYS is not set
Try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.
- waiting for device -
In the end, I found a very useful post here that suggested to manually put the contents of ~/.android/adbkey.pub inside the /data/misc/adb/adb_keys file.
They suggested one of these two methods:
From another working device, copy the adb_keys file into your computer:
# On the other Android device
cp /data/misc/adb/adb_keys /sdcard
# From your computer
adb pull /sdcard/adb_keys .
Then put the working adb_keys file into the problematic Android device's sdcard (using Web or MTP) named as adb_keys, then copy the file into the correct path:
# On the problematic device
cp /sdcard/adb_keys /data/misc/adb/adb_keys
The other method is to simply copy your machine's adbkey.pub from the ~/.android/ directory, and put it into the problematic Android device's sdcard (using Web or MTP) named as adb_keys, then copy the file into the correct path:
# On the problematic device
cp /sdcard/adbkey.pub /data/misc/adb/adb_keys
(Note: there's a similar answer on SO that goes into further details for this method.)
Since I was running a web server on my computer, and I had curl installed on Android, I su'ed from the terminal and ran the following on my Android device:
cd /data/misc/adb
curl 192.168.1.35:8080/adbkey.pub > adb_keys
Killed the adb daemon (using adb kill-server) and BAM! The adb shell worked fine, like it should have been from the beginning.
Hopefully, the method described here works for you as it did for me.

First Remove the adbkey and adbkey.pub from the .android directory in your Home directory.
Make .android directory in your home with 710 permissions: $ chmod 710 .android/ and ownership as: chown -R <user>:<user> .android/. Ex:
$ chmod 710 .android/
$ chown -R ashan:ashan .android/
Go to developer options in your mobile and tap option Revoke USB debugging authorizations
Turn off all USB Debugging and Developer Options in the device and disconnect the device from your machine.
Connect the device again and at first turn on the Developer Options. Then Turn on the USB debugging.
At this point in your mobile, you will get a prompt for asking permission from you. Note: you must check the checkbox always accept from this …. option and click ok.
Now in you machine, start the adb server: adb start-server.
Hopefully when you issue the command: adb devices now, you will see your device ready authorized.

I was hit by this problem, too. I'm using my custom build of AOSP on Nexus 5X. I've added a single line in build/core/main.mk:
diff --git a/core/main.mk b/core/main.mk
index a6f829ab6..555657539 100644
--- a/core/main.mk
+++ b/core/main.mk
## -362,6 +362,8 ## else # !enable_target_debugging
ADDITIONAL_DEFAULT_PROPERTIES += ro.debuggable=0
endif # !enable_target_debugging
+ADDITIONAL_DEFAULT_PROPERTIES += ro.adb.secure=1
+
## eng ##
ifeq ($(TARGET_BUILD_VARIANT),eng)
Now adb shell works fine
Those materials are useful (Chinese articles): http://www.voidcn.com/blog/kc58236582/article/p-6335996.html, http://blog.csdn.net/fanmengke_im/article/details/28389439

Try deleting the adbkey file from C/.android folder
and then run the commands as
mentioned above i.e.
adb kill-server, adb start-server and adb devices
.

Your app is being detected as some harmful program.
Turn off "Verify apps over USB" option. It's in the same view as "USB debugging".

All you need is to authorize debug mode.
1. make sure your Device is connected to your PC.
2. Allow authorized for debug mode via Android-Studio by going to
Run -> Attach debugger to Android process
than you will see the pop up window for allow debug mode in your Device, press OK. done.
i hope it help to someone.

I had the same problem after reinstalled my android studio. Here's what I did to make my adb work again:
-path to C:\Users\User\AppData\Local\Android\sdk\platform-tools
-Shift+r.click and start command from here instead.

for anyone encountering this later this may also help. I encountered this exact issue trying to use adb from a user command prompt and the answers above did not help, but the problem went away with an "adb kill-server" when running in an administrator command prompt.

This worked for me:
rm ~/.android/adbkey.pub
sudo ./adb kill-server
sudo ./adb start-server
sudo ./adb -s emulator-5554 install ~/apk_to_install.apk
I'm not sure if is a good idea run adb with sudo privileges,but it was the only way I get it works. Regards.

I got this as root when as a non-root user I was getting permissions errors trying to connect to custom recovery (Philz). so I killed adb server, copied the .android subdirectory of my user account into /root, chowned -R to root.root, and restarted adb server. I'm in!

Disconnect USB between PC and device
Stop adb server by entering "adb kill-server" in command window
On device use "Revoke USB debugging authorizations" in "Developer Options"
On PC delete "adbkey" file in user directory, for example "C:\Users\Amit\.android"
Reconnect the device to the PC
Open a command window and enter "adb devices". Watch the device's screen for any Authorization message and allow the connection.

I suppose you have enabled On-device Developer Options in your smartphone? If not you can take a look at the steps provided by Android, http://developer.android.com/tools/device.html#developer-device-options

For FIRE STICK 4K it actually says in the dialog:
Otherwise check for a confirmation dialog on your device
Indeed on the TV in the other room there was a confirmation dialog. Doh'!

I had this problem and it wasnt solved by the deleting of any keys (at least deleting them didnt fix it, maybe had an effect after i did fix it though)
I actually had a discrepancy between my sdk-tools version and my Android Studio version. After updating my tools it still didnt work, but after updating AS (to 1.4) everything worked fine again.
Always update both sdk-tools and AS version together ;)

How to solve ADB device unauthorized in Android ADB host device?

When I'm using a rooted Android device as ADB host to send adb command "adb devices" to Samsung S4, I received device unauthorized error message. However when I tried adb to Samsung Galaxy Nexus, it is working fine. Can anyone advise how to solve my Samsung S4 problem?
=========================================
# adb devices
List of devices attached
4d00f9169907301b unauthorized
=========================================
Edit:
Found that this problem only happened to Android 4.2.2 and above. The following link explained that Google has implemented some new security features for using adb.
http://nelenkov.blogspot.com/2013/02/secure-usb-debugging-in-android-422.html
Appreciate if anyone can help on this.

Get the public key from the client phone (adb host)
cat /data/.android/adbkey.pub
copy the above public key to the target phone's /data/misc/adb/adb_keys location. (you may need to stop the adb daemon first with stop adbd)
cat /data/misc/adb/adb_keys
verify both cat outputs match.
try restarting adb daemon on target start adbd or just reboot them.
If you are having problems reading or writing to ADB KEYS in above steps, try setting environment variable ADB_KEYS_PATH with a temporary path (eg: /data/local/tmp). Refer to that link it goes into more details
"On the host, the user public/private key pair is automatically generated,
if it does not exist, when the adb daemon starts and is stored in
$HOME/.android/adb_key(.pub) or in $ANDROID_SDK_HOME on windows. If needed,
the ADB_KEYS_PATH env variable may be set to a :-separated (; under
Windows) list of private keys, e.g. company-wide or vendor keys.
On the device, vendors public keys are installed at build time in
/adb_keys. User-installed keys are stored in /data/misc/adb/adb_keys"

Check and uncheck the USB Debugging option in the device.
If that doesn't work unplug and plug in the USB a couple of times.
At some point, the device should show a message box to ask you to authorize the computer. Click yes and then the device will be authorized.

If anyone has similar issue of having a phone with a cracked screen and has a need to access adb:
Root your phone (mine was already rooted, so I was blessed at least with that).
If you forgot to enable developers mode and your adb isn't running, then do the following:
Reboot your phone into recovery.
Connect the phone with a cable.
Open terminal.
If you type adb devices you should see the device in the list.
If so, type:
adb shell mount /system
abd shell
echo "persist.service.adb.enable=1" >> default.prop
echo "persist.service.debuggable=1" >> default.prop
echo "persist.sys.usb.config=mtp,adb" >> default.prop
echo "persist.service.adb.enable=1" >> /system/build.prop
echo "persist.service.debuggable=1" >> /system/build.prop
echo "persist.sys.usb.config=mtp,adb" >> /system/build.prop
Now if you are going to reboot into your phone android will tell you "oh your adb is working but please tap on this OK button, so we can trust your PC". And obviously if we can't tap on the phone stay in the recovery mode and do the following (assuming you are not in the adb shell mode, if so first type exit):
cd ~/.android
adb push adbkey.pub /data/misc/adb/adb_keys
Hurray, it all should be hunky-dory now! Just reboot the phone and you should be able to access adb when the phone is running:
adb shell reboot
P.S. Was using OS X and Moto X Style that's with the cracked screen.

Have you tried
adb kill-server
adb shell
Sometimes adb gets stuck and first killing adb server and then starting some command forces authorization window to pop-up.
Also please check adb client version on your phone.
THis feature is supported from adb 1.0.31 as far as I remember.

Experience With: ASUS ZENFONE
If at all you have faced Missing Driver for Asus Zenfones
Follow This Link
(http://donandroid.com/how-to-install-adb-interface-drivers-windows-7-xp-vista-623)
I tried with
1) Killing and starting adb server at adb cmd.
2) Switching Usb Debugging on and Off and ...
This is What WORKED with me.
Step 1:Remove Connection with Device and Close Eclipse
Step 2:Navigate to C:/Users/User_name/.android/
Step 3:You Will Find adb_key
Step 4:Just delete it.
Step 5.Connect again and System will ask you Again.
Step 6.Ask Device to remember RSA Key when it Prompts. I think its done.
If you Face The Same Problem after couple of days, just disable and enable USB debugging

For unknown reasons, I only had ~/.android/adbkey, but not ~/.android/adbkey.pub.
I guess that adb was unable to push the public key to the device, and thus the device could never show the authorization dialog.
After killing the adb server, removing the adbkey file and starting adb again, the authorization dialog popped up on the phone.

Try this steps:
unplug device
adb kill-server
adb start-server
plug device
You need to allow Allow USB debugging in your device when popup.

You need to allow Allow USB debugging when the popup shows up when you first connect to the computer!

Delete the folder .android from C:/users/<user name>/.android. It solved the issue for me.

I had to check the box for the debugger on the phone "always allow on this phone". I then did a adb devices and then entered the adb command to clear the adds. It worked fine. Before that, it did not recognize the pm and other commands

For me, the emulator could not have Google Play Services enabled. It could have Google APIs or be x86 or x64 but not google play store.

Try a USB2 port if you're plugged into a USB3 port. At least through the Pixel3 line this makes a difference. Many people have observed the same problem but I'm not sure if anybody knows why. Perhaps there's a way to tell the kernel to not do something USB3-ish on the USB port that the phones can't handle.
I got here because I forgot this workaround, found this page, then remembered to use the other port.

Please follow following steps :
Unplug your phone from system
Go to developer options of the Cellphone and then click on "Allow USB debugging" then please select the radio button prompting "Allow USB debugging when the popup shows up when you first connect to the computer!".....
That's it.. run your command again :
adb devices

You must be prompted in your s4 screen to authorize that computer. You can tell it to remember it. This is for security reasons, occurring in Android 4.4+

I found one solution with Nexus 5, and TWRP installed. Basically format was the only solution I found and I tried all solutions listed here before: ADB Android Device Unauthorized
Ask Google to make backup of your apps. Save all important files you may have on your phone
Please note that I decline all liability in case of failure as what I did was quite risky but worked in my case:
Enable USB debugging in developer option (not sure if it helped as device was unauthorized but still...)
Make sure your phone is connected to computer and you can access storage
Download google img of your nexus: https://developers.google.com/android/nexus/images
unrar your files and places them in a new folder on your computer, name it factory (any name will do).
wipe ALL datas... you will have 0 file in your android accessed from computer.
Then reboot into BOOTLOADER mode... you will have the message "you have no OS installed are you sure you want to reboot ?"
Then execute (double click) the .bat file inside the "factory" folder.
You will see command line detailed installation of the OS. Of course avoid disconnecting cable during this phase...
Phone will take about 5mn to initialize.