: If your device has Secure Boot enabled, a generic prog_emmc_firehose_8936.mbn may not work. The loader must be signed by the manufacturer (e.g., Xiaomi, LG, Alcatel) to be accepted by the BootROM.
: Ensure the file extension is .mbn or .bin and that the binary content starts with an ELF signature or "data ddc".
Because these files are specific to both the chipset and the device manufacturer's signature (if Secure Boot is enabled), it is best to source them from specialized repositories:
