We have managed to share the Official Micromax HS3 Stock Firmware ROM (flash file) on this page. The Firmware Package contains Flash Tool, Driver, Flash File and Instructions manual to flash it.
Micromax HS3 Firmware
How to Flash
Step 1: Download and extract the Micromax HS3 Firmware Package on your computer.
Step 2: After extracting the firmware package, you will be able to get the Flash Tool, USB Driver, Flash File and Instructions Manual.
Step 3: Firstly, install the provided USB Driver on your computer. If in case USB Driver is already installed then SKIP this Step.
Step 4: Then Launch the QFIL Flash Tool on your Computer.
Step 5: Follow the instruction manual to flash the firmware on your Micromax HS3 device.
[*] QFIL Flash Tool: If you are looking for the latest version of QFIL Flash Tool, then head over to QFIL Flash Tool for Windows page.
[*] Backup: Take a backup of everything before flashing the above firmware, as because your personal data will be removed (deleted) permanently after flashing the firmware.
[*] The above firmware (ROM) if Officially released by the Micromax Company. Official ROM helps you to fix the device if in case your device is having any Bootloop, Hang issue, or Dead Issue.