When downloading firmware split into multiple parts (e.g., part01 through part07):
: Use a 4GB or 8GB USB drive formatted to FAT32 .
Once you have the extracted firmware file (typically named allupgrade_538_4G_sos.bin or similar):
: Wait for the process to hit 100%. The TV will usually restart automatically. Do not turn off the power during this process, as it can permanently damage the mainboard.