How to Unlock Samsung Galaxy S 4G

So you bought a Samsung Galaxy S 4G on T-mobile network and wanting to unlock it so that you can use phone on another carrier? You ended up at right place for the guide. Folks at XDA have done it again, they have successfully unlocked Samsung Galaxy S 4G.

UNLOCK SAMSUNG GALAXY S 4G ON T-MOBILE

Before you head to instructions on unlock Samsung Galaxy S 4G, make sure you go through all the requirements!

PREREQUISITES

1. You need to have your Galaxy S 4G rooted to unlock the phone.

2. You also need to have working USB connection between your computer and SGS 4G for transferring file. If you have installed “Kies”, it should take care of necessary USB drivers. Alternatively, download and install Samsung Drivers from below links:

• Download Samsung Drivers for Windows 32-bit version.
• Download Samsung Drivers for Windows 64-bit version.

3. Download and install 010 Editor on your computer. You can install the trial version and use it. Alternatively, you may use any free hex editor such as Hex Editor Neo.

4. Install “Terminal Emulator” app in your Samsung Galaxy S 4G. It is available for free from android market.

FINDING UNLOCK CODE INSTRUCTIONS

1. Launch Terminal Emulator on your SGS 4G and type the following code on at a time:

cd /dev/block

su

2. If you have Superuser app installed, it will prompt for permissions. Tap “Yes”.

3. Now continue in Terminal Emulator with below command:

dd if=/dev/block/bml3 of=/sdcard/bml3.bak

4. Launch 010 Hex Editor in your computer.

6. In 010 Hex Editor, click “View”—> “LineFeeds”—> Custom —> Set Bytes to “32″.

7. Now connect your phone to computer and copy the “bml3.bak” file from phone’s SD card to computer (on desktop).

8. Open “bml3.bak” file using the 010 Hex Editor.

9. Press CRTL and F to search for a Hex string.

10. In the search window pop up, select “Hex byte” in the Type field and then key-in or copy paste following code in the search box:

“FFFFFFFFFF0100000000″

Then click “Find All” button.

11. The number of results may vary from 2 to 10. Go through each result. On the 3rd window pane, against your search term, you should see an 8 digit code. This is your phone’s unlock code! Make sure you note it down correctly!

So finally, after you dug out the unlock code from your Samsung Galaxy S 4G, it’s time now to unlock the device!

UNLOCKING INSTRUCTIONS

1. Power off your SGS 4G and remove the battery.

2. Insert the foreign SIM card on which you want to use the phone.

3. Power on the phone.

4. You will be prompted to enter the “Network Unlock Control Key”. Enter the unlock code that you noted down in step 11 above.

Congrats! Your Samsung Galaxy S 4G should be unlocked now. You can now insert any other carrier SIM card.

Head-over to developer’s thread for more information and to  join discussion.