cell phone

You know the answer to this already.. Though I will only point that out once.
Unlock it at a shop, if you are mobile, some will never be unlocked though most will.

The regulations pertaining to contracts and specific phone securities are provided by shops and if you have to bypass such security, it is morally ambiguous, but not ethically incorrect to use a street trader or online individual to help.

no i did not know the answer thats why i asked the question.

My apologies then...

I assumed in this world that the nature of collective peering, that mobile phone intricacies were mostly grasped by everyone who uses them, sometimes I fail to remember that real people exist... Terrible online and technological curse I have.

It refuses to accept any other SIM card because it is locked to that specific service provider you are with. Your cellphone is an example of a GSM phones that use a SIM card. For you to be able to use any SIM card for your phone, you need to have it unlocked. One famous cellphone that unlocked a countless time is the iPhone. However, presently, there is a law passed that making it illegal but still possible for unlocking.

It is very simple process to get any typed of the network in your handset. Please go to the service center. In the service centre crack the lock of the company. When your mobile has been unlocked. Then you can use in your handset any service provider SIM.