Android ADB device offline, can't issue commands
adb, android, android-2.2-froyo
Solution
I just got the same problem today after my Nexus 7 and Galaxy Nexus were updated to Android 4.2.2.
The thing that fixed it for me was to upgrade the SDK platform-tools to r16.0.1. For me, this version was not displayed in my SDK Manager, so I pulled it down from http://dl.google.com/android/repository/platform-tools_r16.0.1-windows.zip directly.
You then need to rename the `platform-tools` directory and unzip it to `android-sdk-windows/platform-tools`. Using the SDK Manager, I had also updated to the latest sdk-tools before this.
If your whole Eclipse and ADT are ancient, you may need to update them as well, but I didn't need to.
Note: you may need to run SDK Manager twice (once to update itself) before you will see the latest packages.
Problem
I can't connect to my device anymore using ADB through the command line or in Eclipse. Running the command ``` adb devices ``` returns the device name, but it says it's offline. Things I've tried. - Toggled Android debugging mode - Reinstalled the Google USB driver - Restored the OS to a previously working backup (CyanogenMod) - Swapped the USB cord - Rebooted the phone/computer multiple times - Updated the Android SDK I really don't have any clue what's going on. Anything else you think I can try, I'm all ears. To be clear, if you're having this same issue the problem is probably an out-of-date SDK. As of 4.2.2 there is a security feature that requires you to confirm the RSA fingerprint of the connecting device. Open the SDK manager and update the tools! Then reboot.