Share your experience!
After update to Android OS 4.0, i have 2 problem
1. the previous screen capture button is disappear, where is it at os4.0? 
2. my phone getting heat at the back and then stop running. so my only choice is to take the battery out and reopen the phone. will this happens on others ? 
Yes! My Xperia Arc S is freezing to. I only can remove the battery and reboot the phone. It's freezing and it's not reponding to anything. This is what is happening to yours?
I suggest you to format your SD card and reinstall your phone's software
This is how to take screenshot- press and hold power button and volume down button at the same time and hold them there until you take a screenshot 
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Backup everything as it will erase all data on phone (sms, contacts,apps)
Update/Repair your phone via PCC or SUS
PCC (PC COMPANION) – Repair your software with this .First do the setup without connecting your mobile to pc.(only connect when you are asked to).
Do it as follow >> PCC > SUPPORT ZONE> SOFTWARE UPDATE> REPAIR SOFTWARE (written with blue)
PC Companion http://www.sonymobile.com/global-en/tools/pc-companion/
SUS ( Sony Update Service) ... download and install it on pc and follow the on-screen instructions http://www-support-downloads.sonymobile.com/Software%20Downloads/Update_Service_Setup-2.11.12.5.exe
or
http://www.sonymobile.com/global-en/tools/update-service/
Both the links are same
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