To obtain an MT6785 auth file (often required for flashing or unbricking MediaTek devices like the Redmi Note 9 Pro/9S or Realme 6/7), the most common approach is to use an Auth Bypass Tool to remove the need for a physical .auth file altogether. Recommended Bypass Method
Instead of searching for a specific file that is often locked to authorized service accounts, you can bypass the security check using open-source tools:
MTK Auth Bypass Tool: Tools like the MTK Auth Bypass Tool v13 allow you to disable the Secure Boot/DA authentication.
Required Drivers: You must install libusb or USBdk and proper MediaTek USB VCOM drivers to ensure the tool can communicate with the device in BROM mode.
Python Libraries: Some bypass scripts require Python with pyusb, pyserial, and json5 libraries installed. Steps to Use with SP Flash Tool mt6785 auth file
Once the bypass is active, you can use standard flashing software:
Launch Bypass Tool: Connect your device in BROM mode (usually by holding Volume Up + Volume Down while plugging in the USB).
Bypass Auth: Click "Bypass" or "Disable Auth" in your chosen utility. SP Flash Tool Setup: Load your Scatter file from the firmware.
Select the Download Agent (DA) provided with the firmware or a generic MTK_AllInOne_DA.bin. To obtain an MT6785 auth file (often required
In the "Authentication File" slot, you can now leave it blank or use a dummy file since the hardware check is disabled. Supported Features for MT6785
Using these bypass methods on the MT6785 (Helio G90/G95) chipset typically enables:
Flashing Firmware: Writing official ROMs to unbrick devices. FRP Removal: Clearing Factory Reset Protection. Factory Reset: Wiping user data when the screen is locked.
Read/Write RPMB: Accessing secure partitions for advanced repairs. Where to Get a Valid MT6785 Auth File
Warning: Flashing incorrect firmware or using unauthorized tools can permanently brick your device. Always ensure you have the exact firmware for your specific regional model.
Warning: There is no universal “unlock all” Auth file. Each OEM (Xiaomi, Realme, Tecno, etc.) has its own unique authentication keys.
Legitimate Sources:
Third-Party/Paid Sources (Use at your own risk):
redmi_note_8_pro_auth.bin). Verify hashes carefully – malicious Auth files can brick your device.Here are the real-world scenarios where this file is mandatory:
Custom development (e.g., porting TWRP, installing Magisk) requires unlocking the bootloader and often writing an unlocked preloader. The auth file is the gateway to do this.