Unlock your Nokia mobile
Nokia - Connecting People
Many large networks like O2 or Vodafone always lock their phones, so you can only use it on their network, unless you desided to unlock your Nokia phone.
It is usually a simple process of using your phones IMEI number to find the unlock code using the appropriate software! After the software calculated your unlock code you can simply enter it into your phone and it becomes unlocked.
Although Nokia does not support this feature there are plenty of third-party software calculator programs that will generate you an unlock code for free. They usually come with instructions telling you how to enter your free unlock code into your mobile.
Changing your SIM card is useful if you are going out of the country and want to get a prepaid SIM card which only allows a certain amount of minutes, that will work oversees. Dualsim adapter will complement your solution.