Good evening all,
I recently received my Antuino. I installed NEW batteries, but the unit did not power up. I then plugged a powered USB cable into the Antuino and it cam up and worked perfectly. I then started to investigate the battery problem, and found that the battery holder was not allowing one of the batteries to connect at both ends. The plastic battery holder was stiff. If you looked closely, you could see one battery did not connect at both ends. By repositioning the battery, the problem was solved.
This is not a complaint, rather hopefully a short cut if you are having problems after installing batteries.