To use your cell phone on another network, you need to unlock it. This often involves purchasing a Subscriber Identity Memory (SIM) card and an unlock code from your new network provider. However, you will have to pay a fee for this service, especially if you are a new customer.
Unlocking your Nokia phone with unlocking software, or third-party application, can also be an expensive — and sometimes unethical — ordeal. Instead, find a website that will provide you with a free unlock code, using your phone’s International Mobile Equipment Identification (IMEI) number.
Things You’ll Need : IMEI number, Unlock code
Enter *#06# in your phone’s keypad. Press the “OK” button. Write down the 15 or 17 digit IMEI number. Search for a free unlocking website. Examples include Nokia Free, GSM Liberty or UnlockMe (see Resources).
Navigate to the website of your choice. Enter your Nokia’s IMEI number. Select your Nokia’s model from the list. Write down the unlock code. Follow any unlocking instructions provided by the website. Enter the code in your phone and press “OK.” Wait for notification that you have unlocked your phone.