There may come a time that you wish that your Symbian mobile was running as smoothly as when you first got it. Over a period of time, after installing various applications your handset can tend to slow down or be less responsive. Or it may be that you want to clear everything off of the handset before giving it to a new owner.
You can reset your mobile’s software back to how it came when it first left the factory.
Please note that performing the following will wipe all settings, messages, photos and applications you currently have on your phone! Please make sure you know what you are doing before continuing…
Please make sure that you have a backup!
From the home screen enter the below sequence:
*#7370#
You will be prompted to enter your lock password, which on a Nokia is 12345, unless you have changed it previously.

The system will take a few minutes to go through the reset process. Once finished you will be prompted with the set-up Wizard to apply time/location.