: Use a Windows PC to format a USB flash drive to FAT32 .
: Since your file is part of a split RAR archive, ensure all parts (part1.rar, part2.rar, part3.rar) are in the same folder on your computer. Extract the first part; the extraction software will automatically pull data from part 3 to create the final firmware file (usually ending in .bin or .pkg ). Download Toshiba 43U7750 USB Firmware part3 rar
: For many 4K models, official firmware updates are hosted on the Dynabook Support site . : Use a Windows PC to format a USB flash drive to FAT32