System change - how?

Hello,

Normally Symbian phones doesn't need format but a firmware (operating system) update would be good for you.

First go there and install PC Suite
http://www.sonyericsson.com/cws/support/softwaredownloads/detailed/pcsuite/p1i?cc=gb&lc=en

Run it and follow instructions. The very important part is run BACKUP of your phone from it and make sure you backup all data especially in phone memory.

Now when you are sure you have backed up your phone, get and install "Update Service"
http://www.sonyericsson.com/cws/support/softwaredownloads/detailed/updateservice/p1i?cc=gb&lc=en

Follow its instructions. You need a fully charged battery, working USB2 connection cable and a reliable power source (Laptop, UPS all fine).

The important part is backup

If you have latest firmware installed, it will also offer "format" kind of thing and while you may want to do it, it is completely useless unless your phone memory is corrupted etc. That is Symbian, not windows.