If you proceed, treat the 60-second flash window with the same respect as defusing a bomb: no interruptions, no multitasking, no curiosity about what happens if you unplug the mouse.
Toshiba’s PC business is now operated by Dynabook Americas/Sharp . Official support pages have changed. This report assumes the device is using its original motherboard (typically a PLCSF/15F6 or similar for C50-A series). toshiba satellite c50-a bios update