As some of you may know I don't have my phone with me so, above that I have never had a locked phone. So I will try my best here.
The Reason for this How To is the instructions have some people confused.
What I will try to do in this Post is clear some of the things up.
This guide is written assuming the phone is completely Stock, this does not mean it won't help you.
Please Read Everything Before AttemptingPlease Note that you carry out this procedure at your own Risk, I am not to blame. Continue at your own Peril.Requirements:
Root
BusyBox
Internet
Unlock app written by helroz on XDA.
Skip to the Requirement you need.
First Requirement: Root
You need to Root your device. There are many ways to do this, I will be going through the most dependable one.
SuperOneClick.
Please download the Newest Version there.
Put your phone on USB Debug Mode (Settings -> Applications -> Development -> Check USB Debug).
Close Kies and Kies Toolbar App (Kies is necessary for the Drivers).
Open The Application SuperOneClick.exe
Now Plug the Phone in.
DO NOT mount your SD card. Click Root.
Wait a few minutes as it does what it does it can take 2 or 3 tries.
You may need to Restart if doesn't work. (Both Phone and Computer).
Second Requirment: BusyBox
The Easiest Way to do this is Download Titanium Backup.
Open it, it will tell you you need BusyBox and it will tell you to click on the bottom Middle Button. (I think It was called Problem or Fix Problem. I don't Remember).
Once you click that let it do it's magic. it will give you some instructions Like enable the USB Debug do that.
Once it loads up without complaining BusyBox is Installed.
Third Requirement: Internet
Ok this is Obvious I won't go into it.
Fourth Requirement: The Unlock App
Visit this
link, and Download Galaxy_S_Unlock.Zip
Extract this file where ever you want but remember where you extract it.
Plug your phone in Mass Storage Mode.
In Froyo
Settings -> Wireless and Network -> USB -> Ask on Connect
In Eclairs
Settings -> About - > USB -> Ask on Connect
If you are on USB Debug Mode then it doesn't matter.
Select Mount Storage ("I forgot the wordings").
It will either be in the Notification bar (Drag it down) or It will come up after selecting the Mass Storage Mode Option.
Now Copy the Galaxy_S Unlock.apk to the Main Drive of your phone not the External, the internal one.
It doesn't matter which one you go for, it's just easier to find if you put it in the Internal one.
Now safely Remove the drive and Press Turn off on the Phone before removing the phone.
On your phone Look for My Files App and open it.
Look for Galaxy_S Unlock.apk it should be at the bottom of the list.
Click it and Install it.
InstructionsAfter All the requirements are complete Open the newly Installed APP.
(Instructions are copied Directly from the Thread, as I have no way to test it, if someone is willing to add more concise instruction regarding this part please don't hesitate, you will be given Credit).
Click Step 1 save your /efs folder
Click relevant Step 2 Unlock your phone in 60 seconds, black screen is normal
Step 3 Built .nv_data.bak (after restart)
Click Step 4 if you have a problem it will restore /efs folder saved on step 1.
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Let me know if I missed something
If it worked please do 2 Jumping Jacks

and accept my Congratulations

Peace.
IronSingh