Option 1 - O2 Models
1. Turn on the phone with a SIM Card in it that's not the original network. IE It's not currently locked to
2. Enter the Unlocking Code that was sent to you.
(Note: Use the onscreen keyboard and make sure that wireless mode is off)
3. Your phone will now be unlocked
Option 2 - O2 Models
1. Turn on your phone with a SIM Card not from the original network, IE It's not locked to
2. The message 'PUK2' will appear
3. Enter the Unlock Code provided
4. The phone should ask for a New PIN Code, Enter: 0 0 0 0
5. Confirm and type: 0 0 0 0 * * (0 0 0 0 Star Star)
6. Click 'Finish' and the phone will show 'Network is locked ...'
7. Enter the Unlock Code provided and click 'Finish'
8. Restart the phone and it will now be unlocked.