ok here is how you fix this problem. this works coz i have fixed mine!

go to sony ericsson website and download the SERVICE UPDATE to your PC. INSTALL and RUN......CONNECT USB TO PC (NOT PHONE) after installation it will ask you to HOLD BACK BUTTON WHILE INSERTING THE MICRO USB INTO PHONE. FOLLOW INSTRUCTIONS CAREFULLY

The service will download the latest software version for the phone and install it to your phone too. wait for the message that tells you its safe to disconnect the phone...do so and turn back on with sim and memory inserted and ur handset will turn back on and run good as new!!!

Hope this helps and good luck!!

Try to reset your phone. If you can still turn your phone on and off, restart your phone with the power button. Remove and re-insert the SIM card. Restart your phone. If it is still freezing, you may need to update your phone. You can do this using the remote update service. To force restart your phone, hold down the power and lock button keys for five seconds and the phone will automatically restart.Resetting the phone

Warning: Make sure you have a back-up of your important data before you reset the phone, everything will be deleted.

From the Home screen, drag upwards

Select Settings > SD card, USB Mass Storage & phone storage > Factory data reset > Reset phone

Enter your screen unlock pattern

Tap Erase everything

Here is more info on it.

Good Luck and I hope this helps.

Andrew answered correctly, but you must know that if you download the latest software and install it, all software installed in yor phone will be erased.

Anyway, if the service update tells you that your phone is up to date, try to reinstall (repair/fix option). This will install again Android (tm) operating system in your device.

Your phone should work fine then.

my phone freezee and it wont let me connect to that stupid pc companion!

hey have you have an idea for x10 on how to solution the freeze of "Sony Ericsson"???help please

Hey my xperia mini was just stuck at the boot log..i installed pc commpanion and service up...i pressed the power button and the middle square and phone switched off..after dat i held the back button for 30sec and connected the phone to the pc..it took about 5mins and turned green and install flash drivers..after that,it downloaded the update firmware and installed it about 10mins and my phone was restored in full with 2.9 firmware..All glory to GOD..Halla....

Ill try it soon Andrew i think it works.