There are two major communication systems used for cell phones. The CDMA system is a coded response system that ties a phone and its user together to a particular system and to a particular number. The CDMA system is widely used in the United States and a few other countries in the World. The second system is known as GSM. This stands for the Global System for Mobile Communication. The GSM system is becoming more popular in the United States and is the common standard in over two hundred other countries in the World.
The GSM cell phone uses a SIM card to communicate with a particular network. The network providers have the ability to lock the cell phone so that it will not respond to a SIM card from an alternate provider. They do this for competitive purposes, but the practice is deemed unfair by many. When the cell phone is purchased and owned an individual, he should have the ability to change the SIM card and use the phone on any network that he prefers to use. This allows the phone to be used when traveling, especially in foreign countries without paying excessive roaming charges.
So, the question is: how to unlock a cell phone? The first step is to determine the type of phone. If it is a CDMA phone, it does not use a SIM card and there is no need to unlock it. The second step, once you are sure it is a GSM phone, is to determine if it is really locked. The simple way to do this is to borrow a SIM card from a friend with a different service provider and see if this SIM card works in your phone. If you insert the new SIM card, and the phone thinks it is now your friend's phone, it is not locked. If it is locked, you will get some sort of error message.
The next step is to explore the internet and find a reputable company that provides the unlocking code. The company will charge a rather nominal fee to email you the code. The code purely needs to be keyed into the phone to unlock it. You will usually get a rare encouraging message from the phone itself, but in any case, you can test it by using another SIM card as you did in the previous determination process.
Unfortunately, some models of cell phones can not be unlocked with a simple code. The cell phone unlock service that incorporates the codes can determine if your model can be unlocked by code or not. If not, the phone needs to be connected to a piece of hardware via a USB cable to be unlocked. You will need to send the phone away to have done done although this can usually be done sooner rather than an emergency. You can all purchase the hardware and the unlocking software and do it yourself. This method might be the more expensive choice.
An unlocked cell phone is the basic right of its owner. The locking of a GSM phone to make it impossible to choose your own provider is an unfair practice. Fortunately, this is one injustice that can easily be corrected.