Sometimes you will attempt to deploy your application to a device, but the device you want to deploy to isn't shown in the Select Device dialog. This can happen when the Android Debug Bridge decides to go on vacation.

To diagnose this issue, find the adb program, then run:

 adb devices 

If your device isn't present, then you may need to restart the Android Debug Bridge server so that your device can be found:

adb kill-server
adb start-server

HTC Sync software may prevent `adb start-server` from working properly. If the `adb start-server` command doesn't print out which port it's starting on, please exit the HTC Sync software and try restarting the adb server.

Ensure that your device has USB debug mode enabled, if applicable; if this mode is not active then adb will be unable to communicate with your device.