Share your experience!
I alreadly downloaded the update service from offical webiste,
since I have updated to the latest 4.3 system already,
So this didn't work.
What's else can I do, driving me crazy the restarting issue.
Hi and welcome to the community! Since you're new please be sure that you have checked out our Discussion guidelines.
You can try to start your phone in safe mode by press and hold the volume down button during the startup of the phone.
If the behavior persists in safe mode I suggest that you try to repair the phone software using PC Companion.
http://www.sonymobile.com/update
In PC Companion, press start on Support Zone > Start on Update the phone/tablet software > Press the blue link that says "Repair phone/tablet".