Model: SVD1321M2EB

My Duo 13 won't turn on.  The charging light comes on when it's plugged in but the power button doesn't do anything.  If I use a paperclip to press the "Battery off button" after several presses it eventually switches on briefly then turns off again.  It shows the black VAIO screen for a couple of seconds and says "Preparing automatic repair" at the bottom. It shows this for 1-2 seconds then turns off.

How can I fix this?  Lots of valuable data on it & of course I didn't back it up!  It was working perfectly well the evening before but now it's broken.  I'm unning Windows 8.1.  :'(