Answer to: Changed batteries and it doesn't power up after that.I encountered the same problem. I was mislead by the "dummy battery" inside the battery compartment, think that it was positive terminal facing upwards. So naturally when inserted battery with positive terminal facing the lid, it will have wrong polarity. After I reverse the battery terminal, with positive terminal inserted facing down, keyboard works like a charm. Really a silly and misleading design. First it misled me into thinking that there is a third battery stuck inside, second it misled me into aligning the wrong polarity of the battery as I did not notice the polarity when I remove the old batteries. Hope this sharing helps!