http://www.fjsoft.at/en/downloads.php 1) First of all, use My Phone Explorer to back up your sms (from phone memory only), and anything else you want, before updating or resetting the phone, which can be restored back to the phone later.This application can also read your contacts from the SIM card, should you need to back them up, but don't backup your sms onto the memory card, as these will be lost if you update or reset the phone.You can also backup your contacts onto the memory card using the phone only: Main menu--Contacts--highlight New contact--Options--Advanced--Back up to m.card
2) To master reset the phone: Main menu--Settings--General--Master reset: Try the soft reset first(Reset settings) and if this doesn't solve the problem, try a hard reset (Reset all).
3) To take the battery out, you need to prise it gently but firmly, from the bottom.To update/re-install the software, switch the phone off, open up the SE update service application and when prompted, simultaneously press the C button and connect the USB cable until the update service recognises your phone which should only take a few seconds.You can also update the phone over the air without a PC: Main menu--Settings-General--Update service--Search for update: If you are told that you already have the latest software, then you will need to use the PC method to re-install the software.
