To perform Xperia X2 hard reset:
Power on the phone and press Win key + O.
Then press W for clean boot, then WIN key again.
X2 phone menu
1. Select Start > Settings > System > Clear phone memory.
2. Follow the instructions.
A hard reset will reset your phone to factory default settings. All files and configurations that you have entered in the phone will be lost. After the hard reset the phone will reinstall Windows Mobile and the software included.
Note: Backup the files that you want to keep, before you perform a hard reset. You can backup files via a computer or a memory card.
x2 firmware update with PC companion softwareDownload PC companion and install
Install PC companion on your PC computer. Follow instruction. For firmware update you need a micro USB cable. When the pc recognizing your XPERIA X2 it will install the necessary driver files.
After yourXPERIA X2 connected press Start / in Support Zone
You can also use Sony Ericsson update service tool
PC Suite is out of date use PC companion software instead
If nothing works: As last resort do a Sony Ericsson phone repaire with PC Suite. Use this method to hard reset AFTER INSTALLATION----> TOOLS > PHONE REPAIR