This article explains how you can set up the device lock in a mobile device running on a Symbian operating system.
Anti-theft can automatically lock your device when the SIM card in the device is changed. The locked device can be unlocked only with your lock code.
Setting up the device lock
To set up the device lock:
Browse to Settings and press the selection key.
Select Anti-theft in the settings selection list.
Enter a Lock code. The lock code needs to be at least 5 characters long. Store it in a safe place. Note: Your lock code protects the Anti-theft settings. You have to enter your current lock code before you can change any Anti-theft settings.
If you want to lock your device when a SIM card changes, select Yes on Lock when SIM changed.
When someone inserts a new SIM card into the device and the SIM change lock is turned on, the device asks for the lock code before it can be used.
Unlocking the locked device
To unlock the locked device, enter your lock code.