Unlocking a MediaTek device is not as simple as typing in a number. It usually involves a process called or "Modem Formatting."
Insert a SIM card from a different carrier. If the signal bars appear and you can make a call, the MTK Network Unlock Tool succeeded. mtk network unlock tool
before attempting any network unlock, as errors can lead to a permanent loss of cellular signal. Legal & Safety Notice Unlocking a MediaTek device is not as simple
| Error Message | Cause | Solution | | :--- | :--- | :--- | | "ERROR: S_BROM_CMD_STARTCMD_FAIL" | USB driver conflict (libusb vs. MTK) | Use UsbDk or Zadig to install WinUSB driver for the BROM device. | | "DA sent successfully, but no response" | Wrong preloader; Security on chip (Mt6739+) | Use newer mtkclient (v2.0+) with exploit bypass ( --brom-low-level flag). | | "Phone shows 'Factory mode' after reboot" | Accidentally wrote wrong NVRAM size | Restore backup via tool. If no backup, flash stock firmware via SP Flash Tool. | | "Unlock says OK, but SIM still locked" | The lock is stored in two places (NVRAM + Protect_F) | Use "Advanced Unlock" or "Erase Protect_F partition" (dangerous). | before attempting any network unlock, as errors can