User guide

YOUR PERSONAL SETTINGS
LOCKING YOUR TREO 750 AND INFO
218
12
CHAPTER
Locking the SIM card
You can lock your SIM (Subscriber Identity
Module) card to prevent unauthorized use
of your mobile account. When your SIM
card is locked, you must enter the PIN to
power on your phone to make or receive
calls, except for emergency numbers. The
SIM card remains locked even if you move
the card to another phone.
When your SIM card is locked, you can
unlock your SIM card by trying to turn on
the phone. A dial pad appears for you to
enter your PIN.
BEFORE YOU BEGIN You need the
following:
• Make sure your phone is on and that
you’re inside a coverage area (see
Turning your Palm
® Treo™ 750 smart
device on/off).
• Get your default PIN from AT&T
1 Press Start and select Settings.
2 On the Personal tab, select Phone .
3 Select the Security tab.
4 Check the Require PIN when phone is
used box.
5 Enter the PIN and press Done
(left action key).
6 Press OK to finish.
7 Turn your phone off to activate the
phone lock feature.
Your SIM card locks when you turn off your
phone and turn it back on. When your SIM
card is locked, you can unlock your SIM
card entering your PIN.