I tried the G-sensor calibration test on my HTC One M9 (as described previously) but it failed repeatedly. I then tried dropping it on its top edge onto a thin carpet from about 6 inches. Tried the test again and it was successful! :)
My HTC DNA was showing zero signs of life. This worked for me too after I had exhausted all the other tips!!!!! :) Thanks so much for everyone's input!
Some additional advice should you try this:
First remove the SIM card using a paper clip. Removing the back off your HTC DNA isn't easy. To...