Share your experience!
Hello,
Now, new problem arrive in my Sony Xperial SL Lt26ii, Suddenly only Emergency Call window appearing in every boot, all menu, wallpaper, messaging ,Phone Disappear now. Touchscreen also not working.
I have latest update Build: 6.1.A.2.55
My phone almost dead 
IMEI nr:353617051166142
I suggest that you try to run a software reinstall using SUS.
http://www.sonymobile.com/gb/tools/update-service/
If the problem still remains you should contact your local support team, to have the phone examined and fixed at an repair center.
http://www.sonymobile.com/global-en/support/contact-us/contact-info/