Unlocking Bootloader on GT-I9060I

Hi

I've had some hard time trying to unlock my GT-I9060I's bootloader (so I can install unsigned custom ROMs) but I didn't succeed.
Thins I've tried so far:

• Installed Android SDK


• Installed ADB and Fastboot drivers


• Changed the android driver to Android Bootloader Interface

The problem seems to either be my computer not recognizing the phone in fastboot mode or simply my phone not booting in fastboot mode (even though

HTML Code:

---

adb reboot bootloader

---

rebooted my phone)
How can I unlock my bootloader?