For almost a year I have searched a way to unlock my Samsung smartphone. I bought this phone locked in Vodafone network and the costs requested by the vendor to unlocked the phone were too prohibitive (50 eur ???). Now I finally manage to unlock it. Below I will try to synthesize the steps followed by me in order to unlock my phone. The model used was Samsung GT-I5500 but the smart guys that discover the way to unlock the phones say that this method can be applied to many other Samsung smartphones.
How to unlock Samsung GT-I5500:
1. first root the phone (this can be undone after you unlock the phone)
2. extract an image file from phone to pc
3. search the unlock code in the extracted file
4. optional: unroot the phone
5. turn off the phone, change the SIM card with the SIM belonging to another network, turn the phone on, enter the unlocked code searched and you are set.
Now the above steps developed:
1. Root the phone:
In order to root the phone I used the recomanded tool SuperOneClick
1.1. Download the app
1.2. Unzip donloaded file
1.3. Connect phone with PC by USB (default kies mode)
1.4. Put your phone on USB Debugging mode (Settings -> Applications -> Development -> USB debugging [X])
1.5. DO NOT mount your SD card
1.6. Run the SuperOneClick app
1.7. Click on Root button
2. Extract a specific file from the phone
There are 2 methods available. I used the first.
2.1. First you should install Android SDK Tools: http://developer.android.com/sdk/index.html
2.1.1. Download and isntall the Android SDK.
2.1.2. Run SKD Manager and install all necessary packages.
2.1.3. You will only need ADB Shell from the Android SDK Tools
2.2. Open one instance of "Command Prompt" and go to folder containing ADB tool (adb.exe). (e.g C:\Program Files (x86)\Android\android-sdk\platform-tools>)
2.3. Make sure your phone is connected to PC and "USB Debugging" it's enabled. Make sure that you enabled the SD card
2.4. The following commands will be executed in "Command Prompt" that we opened earlier:
2.4.1. adb shell
wait the # prompter to appear after each command
2.4.3. cat /dev/block/bml5>/sdcard/bml5.img
2.4.4. exit (2x)
2.4.5. adb pull /sdcard/bml5.img
2.5. The file that we copied to PC should be in C:\Users\~username~\AppData\Local\VirtualStore but you can do a quick search to find it.
3. Search the unlock code into the extracted file
Use any editor that supports HEX View. I have used the Notpad++ with HEX Editod plugin.
3.1. search for
FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF 30 30 30 30 30 30 30 30
3.2. Above this string you should see the unlock code which will be 8 digits plain text surrounded by unknown symbols.
3.3. If the code is not found from the first search, search again.
4. Unroot the phone (Optional)
You may want to unroot your phone back tho the initial unrooted state.
4.1. Run the steps from 1.3 to 1.6
4.2. Press Unroot button.
5. Unlock the phone
The last step from this tutorial is to actually unlock the phone.
5.1. Turn off the phone
5.2. Change current SIM with a SIM belonging to another network
5.3. Turn the phone on
5.4. Enter the unlocked code searched
Now you should have an unlocked smartphone and you can use any SIM card from different networks.