Sony Xperia C Stock in red light

Hello everyone
I have a problem in the device (Sony Xperia C)

When connected to the computer for software,computer detect it for Moment then did not detect it (unknown device)

I download all drivers

But not respond device

This message appears when I use a flashtool:

usb\vid_0fce&pid_d1a0&2a931f3&0&2 Driver installed :false

Please help