: Do not turn off or unplug the TV during the update. Interrupting a firmware flash can "brick" the device, making it permanently unbootable.
: Keep holding the button until a "Software Upgrading" progress bar appears or the standby LED begins to blink rapidly. Download IRIS SAT 42E790S Firmware USB part1 rar
: Use a tool like WinRAR or 7-Zip to extract part1.rar . If all parts are in the same folder, the software will automatically combine them into a single firmware file, often named MstarUpgrade.bin or similar. 2. USB Drive Requirements : Do not turn off or unplug the TV during the update