Unlocking a cell phone can be quite tricky. It is better to give it to a cell phone retailer or repairer. He will do a much better job and with no hassles. He may charge a small fee in return. Though, here are some ways of doing it yourself. First, call your service provider and request for the unlocking code. This is the best way of unlocking the phone. The other way is to download unlocking software from the internet. These softwares are usually available for free or you have to pay through credit card. After you have got the software, write down the serial number or the IMEI number if you are using a Nokia handset. You can get the number by entering *#06# on your phone. Also enter the country and the network. After entering all these details, the software will generate a code. Enter the code on your phone and your phone shall unlock.
You can unlock your cell phone in two ways: Firstly you can release your phone if it is of a kind which can be unlocked just by typing in a secret code. The secret code is generally a distinctive number which can be used only for that solitary phone, almost like an identification number. The code is generally associated with the serial number of the phone as well as the service provider. One can find out the codes for most Nokia and some other phones from many pay sites over the internet.
Secondly, if you have a phone which requires its 'firmware', which is basically the software of the related operating structure, you need to type that out to unlock it. For this you would need to link the phone by a special data cord to a special programming system. This service can also be found on pay sites online.