Develop Reference

ADB No Devices Found / Tablet restart

I have andoroid tablet which starts only to boot screen. No combination of power and vol +/- leads to recovery. Tablet is responsible when connected to PC. So I would like to try reset is via ADB.
When I connect tablet to PC, it apears for few second in device manager. I was able to install driver and now it apears as MediaTek PreLoader USB VCom. But unfortunately only for few seconds.
So when I run ADB.exe devices - list of attached devices is empty. adb server is running.
Any tips what to try please?
Thank you

Try checking if you have the appropriate adb driver installed for your tablet.
Also, I recommend using Universal ADB Driver. It works for pretty much any android device.
However, you must have ADB options enabled beforehand on your tablet (before it went unresponsive). Otherwise, ADB will not be of any use to you.

HTC One M7 - Unauthorized in adb

After 10 hours spent, it seems that I need to remove /data/misc/adb/adb_key file and restart the phone. But how can I do it if phone is unrooted and adb has no access?
It's unrooted HTC One M7 Att. I've tried reinstalling drivers many times and reinstalling sdk. I plugged and unplugged usb, changed ports, turned on and off debugging. Nothing helps and rsa dialog doesn't come up. I've also deleted adbkey files in .Android folder on Windows.
I've connected another HTC One and it worked smoothly. So, problem in the phone.
Help?

If your device appears in adb devices output (even as "unauthorized") - your drivers are fine. Also there's no need to reinstall the whole SDK - just make sure you have updated platform-tools package to the latest version.
unplug your device
kill adb (or just reboot your PC)
start adb
make sure your device is unlocked at the idle (launcher) screen
plug your device back in
you should see the authorization dialog now.

that means that you need to confirm the connection on the device (in your case the htc m7).
A Dialog should be displayed on the device (e.g Image below) when you connect to your device.

There is an alternative.....
You can connect it using adb wireless app and debug your apps wirelessly...:)
following is app link.....
https://play.google.com/store/apps/details?id=za.co.henry.hsu.adbwirelessbyhenry&hl=en

4.2.2 Android Eclipse Unknown

Ever since 4.2.2 - Eclipse shows "unknown" for my device when I pull it in. Here is what I have done:
Updated Android SDK to newest release (21.1, 16.0.2 - Tools, ADB 1.0.29)
Attempted to turn the phone on and off again
Toggle Debug Mode on and off again
There is only profile on the phone
Different USB / Ports
Reboot numerous times.
Any luck here?
UPDATE:
Device ID: 014E1F310600E01D offline

you didn't specify your device name and model number. i think you didn't install driver for your mobile device. if you already installed it automatically detects your device. To allow app installs from non-Market apps, tap the menu button on your home screen, then choose Settings >> Applications >> Unknown sources.

I'd forget about ADB connections that use USB as a means of transport. I've had nothing but problems with it, using several devices from several different manufacturers. Look in the play store for 'ADB wireless' apps. Those allow you to set up the same connection using WIFI.
At the moment I'm developing an app and have three devices connected to ADB this way. Works like a charm and is much more reliable

I found out that the PATH was pointing to the old adb (before the update (1.0.29), but once I went to /platform-tools/adb (by running ./adb devices) - everything worked out and now the device is active.
Hope this helps others!

I changed USB port and it worked as well for me.

You have to restart ADB and if there is any notification on the device screen you have to accept it.
Resolution :
After opening eclipse and before debugging, open the cmd then run " adb kill-server "
then wait 2-3 seconds then run " adb start-server ", then try to run the program again you will find your device is online.
i hope that helps

Android and Eclipse: I can't able to find my device LG-E720 from Run/Debug Configuration/Android Device

As title, I can't able to find my phone device into Eclipse.
I activated on the my phone, either Application/Unknown Source and Application/Development/Debug USB.
But into Eclipse not appear any device phone, why?
Thanks'

Go to the cmd prompt, and then take it to the platform-tools.
Then type the commands
adb kill-server
and then
adb start-server
Then to list the connected devices,
adb devices
you will see the list of active devices including the emulator. If the device is not present, continue the steps for some time..
After you get the device listed among the active ones, you can run it in debug mode.
Think, this will help you..! :)

I just had the same problem on 2 of my phones (Nexus 1 and Amaze 4G). After some research I found that people try to overcome this by restarting Eclipse and ADB (only Eclipse won't do) but it took me rebooting the system and phone to make it work again. If you can go to Eclipse->Window->Open Perspective->DDMS and see if your phone shows there with red bug icon next to your app. If so then try what I described above. If you don't see your device in DDMS perspective then it's your USB driver that is not working and needs to be reinstalled

Had a similar problem with my LG P520. In my case, the problem was as a result of me setting the minimum Android level to Android 2.3(9) while the phone was a Froyo/Android 2.2(8) phone. Hence, it was not a compatible device and would hence not be shown in list of compatible devices.

connect your PC with internet may be it will install some software to connect it with the phone debugger and make sure you enable the usb debugging on your phone.

Adb stops detecting my phone after a while

I am developing for android on a linux machine and I have already created a udev rule for android and it works. After a while if I unplug the device and plug it back in again, adb doesn't recognize the device if I run lusb or dmesg to get information about the device. I tried reload the udev rules and it does not work, I even tried to kill the adb process but it still does not work.
Can someone help?
Anyway, thank you.

This appears to be a real problem on linux, at some point in time a device will no longer be seen by the ADB. What I should really say is almost never be seen by the ADB. In my case I have a Samsung Galaxy Tab 10.1 that was given to attendees of Google I/O 2011. My Ubuntu 10.10 development system was working just fine with this device. Sometime near September 19th the ADB stopped seeing the device! In fact there have been breif moments in time when the device was detected by the ADB. What needs to be made clear about the problem that I and I believe pharaoh are having is not the permissions issue where executing
$adb devices
returns ?????????? for a device. The device simply does not show up in the list. One more important fact is that at no point in time has this device not been detected on my Windows based development machines.
It appears to me that the mechanism that the ADB uses to determine if a device on the USB is in fact a adb_device is fragile and some change in either our devices or our development systems has broken this detection.

Due to some reason sometimes adb gets disconnected, so in that case you have to restart the adb.
Go to DDMS->Devices and you will see Reset adb option in View Menu besides Screen Capture option.

I usually have this problem due to I have installed the adb plugin on Chrome. If I close Chrome and re-connect the device, it appears listed with adb. Hope this helps.

I just had this problem as well with my OnePlus 2.
It was working the previous day. I had then set up port-forwarding using the 'device inspector' dialog in Chrome DevTools. It's supposed to be kept open for it to work, so I kept it open in a tab permanently.
The next day when I connected my device via USB, adb devices didn't list anything. I closed the device inspector dialog in my devtools and suddenly adb recognized my device again. I re-enabled port forwarding after this, but my device is stll being detected.
tl;dr: Close your port-forwarding dialog in Chrome DevTools if it had been kept open even after you removed your device.

I've had this happen before. I disable, and then re-enable debugging on the phone (Setting -> Applications -> Development -> USB debugging, uncheck, then re-check) to get it recognized by adb again.

Try adb kill-server to stop the adb and use another command 'adb devices' to restart it. It should work and it should detect your device again. ( For those who can edit my post: any other commands will start the server not just adb start-server, so don't edit without to leave a comment at least)

May be stupid, but I have been had similar problem right now and after an hour I noticed that the problem was that my USB hub, in which such devices are connected, were not actually connected to the PC.
In fact, the USB wire WAS connected, but they may not being doing good contact for some reason, so it failed randomly from time to time.

Same problem here, using mac os. However connected devices are recognized by Android File Transfer application. It all started with S3 phone (rooted), I thought something wrong with the phone, because Nexus 7 (stock) worked as intended. After 3 days of connecting/reconnecting it stopped being recognized by adb too. Tried to perform a hard reset - didn't help.
adb list - empty list
android file transfer - works perfectly
I'll run out of devices soon

Same problem observed on ubuntu, I tried the following and it worked:
Reference: link
Use the command udevadm from the above reference for ex:
"sudo udevadm test --action="SUBSYSTEM=="usb", ENV{ID_VENDOR_ID}=="[vendor_id]", ENV{ID_MODEL_ID}=="[model_id]" MODE="0666", SYMLINK+="[Device_Name]"" $(udevadm info -q path -n /dev/bus/usb/001/[DevNum])"
This seems to fix some link files and that solved the problem of adb not detecting device after a while.