Default [Q] XTS can't connect to Wi-Fi

Hi everyone.
Yesterday my tablet Sony XTS couldn't connect to my Wi-Fi network. so, i turned off and on and still couldn't connect to any network... i tried sharing Wi-Fi from my 3g network in my phone, but still couldn't connect. Sooooooo i freak out, and tried a hard reset.... And guess what ?
It couldn't connect

¿What can i do? Please HELP , this tablet belong to me since july 2013... is warranty still available?