1) What are the advantages of unlocking your phone?
When you purchase your phone many people are not aware that there is a good chance that your network provider has locked the handset to accept only SIM cards from its network.
For example if you purchased a handset that is locked to Vodafone it will not work with a SIM card from T-Mobile, O2 or Orange etc..

In many peoples opinion this is unfair. If you unlock your phone you can then change your SIM card to that of a different network provider. But why would you want to unlock your phone? I have listed the 4 main reasons below:

i) You may own more than one SIM card running on different networks, if you want to swap the SIM cards from time to time your phone must be unlocked.
ii) You may find your network is not as competitively priced as another and you would then need to put a different SIM card into the phone.
iii) If you are travelling overseas you may want to use your phone with a SIM card from that country to save yourself money.
iv) You may be looking to sell your old handset, in which case you will be able to sell it at a higher price and not have to worry if your potential buyers SIM card will be accepted by your handset.

2) How do I check to see if my phone is locked?
The simplest way to check if your phone is locked is to insert a SIM card from another network and see if the phone will accept it. If your phone is locked you will often see an error message of some kind. These messages vary depending on your handset manufacturer:
Nokia = "Enter restriction code" or "SIM card rejected"
Motorola = "Enter special code"
Ericsson = "Enter Correct SIM"
Sony Ericsson = "Incorrect SIM"
Samsung = "Invalid Network SIM...Enter Code"
Panasonic = "Invalid SIM"
Siemens = "Phone disabled! NETWORK LOCK"
Sharp = "Invalid Network SIM"

If you do not have access to a SIM card from another network then there is a less scientific method you can use to check if your handset is locked. Simply look to see if your network has placed their logo on your phone somewhere. For example in the UK orange always lock their handsets and they always "badge" their phones with their own Orange logo either on the front or the back of the handset. It is a sure give away that the network has customised the handset to their requirements which means they have also locked it!

3) Is unlocking illegal?
NO, it is a common misconception that unlocking your phone is illegal!!! In fact quite the opposite, it is your consumer right to have your handset unlocked. The networks have to provide you with an unlock code if you request it. BUT they normally charge approximately £35!!!

4) What is remote unlocking?
Remote unlocking has now become the most common way to unlock your Nokia Phone. This is because it is so simple and no data cables are required at all! All you need to do is type a specially calculated code into the phone! It's that simple!
To calculate the correct code you will need to know the:
1) The model of your handset (e.g. 7210),
2) The handset's specific serial number (IMEI number - 15 digits long)
3) Which network the handset is locked to!

5) Is remote unlocking safe?
YES it is 100% safe! It is very easy and safe to unlock your phone using unlock codes, in fact this is how the networks themselves unlock their customers handsets.

6) I can't enter the final # of my unlock code, why?
The chances are you are try to unlock a DCT3 Nokia. The codes that are generated will only unlock DCT4 Nokia's.

7) I have entered an incorrect code more than 5 times. I see the message "cannot undo restriction" or "not allowed" when i enter the code, what now?
If you see any of the above messages then you have entered an incorrect code more than 5 times! When entering unlock codes you only get 5 attempts. There is no free solution to unlock your phone if you have entered the incorrect code to many times. The best advice I can offer is to take your phone to a professional unlocker such as a market trader or small independent retailer. They will use a direct unlock method using either a data cable or clip. These solutions are normally quite expensive to buy and unless you plan to unlock many phones it is not cost effective to purchase these yoursel

Unlocking Glossary & Definitions

MCC = Mobile Country Code

MNC = Mobile Network Code

DCT = Digital Core Technology

GSM = Global System for Mobile Communications

IMEI = International Mobile Equipment Identity (number)

UEM = Universal Energy Management

OTP = One Time Programmable

SIM = Subscriber Identity Module

CDMA = Code Division Multiple Access

MCU = Master control unit

PPM = Post Programmable Memory

EEPROM = Electronically Erasable programmable Read Only Memory