ZEDRAY

The official instructions for using your Android phone for development are here:
http://developer.android.com/guide/developing/device.html

So you plugged your Android phone into your Windows machine having forgotten to switch on USB debugging…
Menu > Settings > Applications > Development > USB debugging

Then Windows detected your device as a USB-Mass storage device and won’t change the settings, regardless of how many times you uninstalled the device. Thread on it here.

This solution worked for me and didn’t require editing the registry settings (I don’t know if the reboot is unnecessary).

(1) Plugin phone
(2) Uninstall any drivers that mention “HTC Android Mobile USB Device”
(3) Unplug phone and restart
(4) Install and run USBDeview
http://www.nirsoft.net/utils/usb_devices_view.html
(5) Using USBDeview find the Android device (for some reason Windows hides uninstalled drivers instead of deleting them), right click on it and uninstall.
(6) Follow the official instructions to the letter this time.
http://developer.android.com/guide/developing/device.html

Happy developing.