This is tutorial for giving your death phone live again.
Note : Mini owners, hold center button and power button for a few seconds to shut down your phone. If that doesn’t work, go here
First attempt, try booting to recovery. If you can, select backup and restore.
If you can’t, then you have to reinstall either using the pc suite or the Sony Ericsson Update Service to reinstall the software.
When that fail, you resort to flashtool
Now download both the flashtool and software file (make sure you pick the right one) to your pc.
Extract flashtool and you get a flashtool folder.
Extract the file and you got a folder.
Place that folder on the flashtool folder.
select flash and click on the folder you just put in.
Then you connect the USB to your phone (must be shutted down first) while holding back button.
Once the led flash green, you can let go and let it complete the flash and you will have stock software again.
Tips : If for some reason your phone kept on booting on, you pull the battery. Run the flashtool. Ready yourself, put on the battery, and quickly connect the usb while holding back button. Yes it require sleight of hands but it work.