Iam useing sony ericsson w850i for past 1 year.suddenly one day it was switched off if i seem to turn on it is flashing the red light.and now iam not useing that phone any ideas to turn on my phone back.

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Red light is flashes Due to the low battery
Your battery is not enough charge to switch ON
so firstly Charge your mobile phone when it is enough charge to Switch ON then Switches it ON...
there is not any hardware or software related problem
so do it..

if the problem resolves then
VOTE ME

Hello,

from my own experience and idea, I think that flashing light indicates low battery.

This is usually common with Sony ericsson phone, it flashes a red light once battery is low and you want to power is on.

Maybe should test your phone with another battery.

All the best.