Information
On applicable phones, SIM cards often contain contact and other personal information. This setting will lock the SIM card so that it requires a PIN to access.
Solution
On the Android device,
1. Press the Menu button.
2. Tap System settings.
3. Scroll to Personal.
4. Tap Security.
5. Scroll to SIM card lock.
6. Tap Set up SIM card lock.
7. Check 'Lock SIM card' if not already checked.
8. Tap Change SIM PIN.
9. Type old SIM PIN if requested.
10. Tap OK.
11. Type in new SIM PIN.
12. Tap OK.
13. Re-type new SIM PIN.
14. Tap OK.