Power on the TV. Many Vestel TVs auto-detect firmware on boot and display an update prompt. If nothing appears, try holding the front-panel power/button or the Remote’s OK/Menu during power-on (follow model-specific procedure).
Accept or confirm update. Do not power off or remove USB during the process.
TV will reboot several times and finish installation.
Recovery/Service mode (if device won’t boot): Specific key combos (e.g., holding MENU+VOL+POWER) or using a serial/USB-to-TTL connection and service tools. This is advanced — consult service manual. Toshiba UK (Support > Downloads > Enter model number)