Firmware update or recovery from a USB drive (Samsung, LG)

Samsung and LG let you load the model's update file from a USB stick. The format and folder rules are strict; most failures are a wrong file, wrong folder or wrong format.

Cross-checked ~30 min easyBrands: Samsung, LG

Before you start

Do not turn off or unplug the TV during the update.
Use only the official file for the exact model.

Diagnostic steps

Unlock all 4 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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