Android device not regonized ?

Borrowed from Stackoverflow . Keeping it here for my ready reference

http://stackoverflow.com/questions/7594975/why-is-eclipse-and-adb-not-recognizing-my-android-device

First, check the kind of quotes you are using in your udev rules. It looks like you might be using non-ASCII double quotes. See the difference between the quotes around usb and usb_device, etc.

UBSYSTEM=="usb", SYSFS{idVendor}=="1bbb", MODE="0666"
SUBSYSTEM==”usb_device”, SYSFS{idVendor}==”1bbb”, MODE="0666"

You can also just use sudo with ADB, as suggested by @JeremyD. Doing that makes this file essentially irrelevant.

Second,

1. Edit ~/.android/adb_usb.ini (or if you are running as root, check /root/.android)
2. Add 0x1bbb to the end of the file if it already exists, otherwise do: echo 0x1bbb >> adb_usb.ini
3. adb kill-server
4. adb start-server
5. Check output of adb devices for your device