Bypass the SP lock With a Nokia 16xx/21xx/31xx/51xx/81xx
1. Insert SIM card of different provider.
2. Turn on the phone and press the UP VOLUME key for 3 sec.
Then release it and the phone says PIN CODE?
3. Press the "C" key.
4. Then Press * and wait until it disappears and appears again, then press
* one more time and 04*PIN*PIN*PIN#