Use a high-quality USB drive formatted to FAT32 .
Large firmware files are often split into smaller "Parts" (e.g., Part 1 to Part 12) for easier uploading and downloading on file-sharing sites. .rar (Requires WinRAR or 7-Zip to extract). Download MICROMAX L40CANVAS Firmware USB part12 rar
The TV should show an "Upgrading" or "Software Updating" screen. Do not turn off the power during this process. Use a high-quality USB drive formatted to FAT32