Yesterday my K750i only showed white screen when trying to start after changing SIM card. No response - it just would not turn on. With no hope of an answer, I called customer support at SE. They told me to update the OS with software from SE website.
After an odd procedure of taking SIM out, attaching USB while pressing (C), the phone went through a 15 minute OS upgrade. And wonders of all wonders, it actually worked. New OS installed and my phone back in business.
My guess is that this - dead phone - will happen to many SE users, and quite a few will buy a new one. As it turned out, that was not necessary. From temporarily hating SE a couple of hours ago, I am now a great fan!
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