A firmware file is used to reinstall the operating system in your device. It's basically a set of instructions that are stored in the flash ROM of a hardware device. If you are facing issues like the application stopped working, an IMEI issue, and the phone not working, you can use a firmware file to fix the issues. With the flash file, you will get back your mobile in factory format.If you are looking for how to use infocus m430 flash tool, you can visit this link for a complete guide. https://firmwareflashfiles.com/infocus-m430/