First, Turn Wireless Mode Off:
 
   1. Scroll to the Airplane Icon (Turn Wireless Off.)
   2. Press Select.
   3. Wireless mode will turn off.
   4. Remove the SIM card
   5. Power on the device (put the battery back in)

Unlock Instructions:

1.   Insert SIM into device.
2.   Change phone to GSM mode.
3.   Power phone on and turn off the radio (turn Wireless Off option). This is very important!
4.   Select Options, then Advanced Options.
5.   Scroll down and select SIM Card.
6.   Type "MEPPD" (please note that you will not see what you type on the screen).
7.   Type "MEPP then [ALT BUTTON] then "2" (please note that you will not see what you type on the screen).
8.   You should be presented with a prompt "Enter Network MEP Code".
9.   Type in the 16 or 8 digit unlock code.
10. Once complete, make sure the entered code is correct and hit Enter or Return or press OK.
11. Reboot device.
 

If you cannot find the ALT key on the European BlackBerry Pearl 9105, please follow these instructions:

The 9105 doesn’t have an ALT key, however you can put it into ALT mode. To activate ALT mode you must do the following: Press the right side Volume keys in the following sequence: up, down, up, down, up. The Alt icon should display in the top left corner of the screen. Note: If you press the Shift key it disables the ALT mode so it’s impossible to enter ALT-SHIFT-H.
 
IMPORTANT: If you get a 'Code Error' message do NOT keep trying because you only have limited attempts. Please check the IMEI, Network, Network Country, and contact your seller.