K610i I cant switch on my K610, when i try to awitch on the light on top of the phone flashes red

Got that same problem before with my sony handset. It may be a virus or a software problem.
Basic troubleshooting steps.
1. Remove battery for 5 mins insert and turn on. Make sure battery is not empty.
2. Run a virus scan on your phone.
if nothing happens just bring it to a nearest repair store. Still under warranty period? also bring it with you reciept to a nearest Sony Repair Store.