How can I reset AirPort Express to factory defaults? I tried the, press reset and power it down without success. All I got was to make it do yellow blinking. If I release the reset the blinking slops, anyways it stops even without releasing the button after 30 seconds.

The problem is that AirPort utility is not able to detect it and no Wireless is started.

What else should I try to reset this white brick?
I believe the full procedure is


Unplug the unit
Press and hold reset (e.g. with paper clip)
Plug the unit back into power outlet (while pressing reset)
Wait for rapid green flashing
Release reset button


From your description, it's not clear how you were managing the AC power