How do I fix “mode not supported” when using a network TV box with a Samsung TV?
Answer
This usually means the TV and network box are not agreeing on a signal format after a bad handshake. Powering both off, unplugging them for a full minute, then starting the TV before the box often clears the message.
Before you start: stop right away if…
- Unplug devices carefully and keep power cables dry and clear of damage.
Follow these steps
Turn both devices off
Turn off the Samsung TV and the network TV box with their power buttons or remotes.
You should see: Both devices are off before you unplug them.
Unplug both for one minute
Unplug the TV and the network TV box from power and leave them disconnected for one full minute.
You should see: Residual power clears and both devices are fully powered down.
Power the TV first
Plug the TV back in first, turn it on, and select the HDMI input used by the network box.
You should see: The TV starts on the correct input and is ready for a new signal.
Reconnect the network box
Wait about 15 seconds, then plug in and turn on the network TV box. Wait for it to finish booting before changing inputs again.
You should see: A normal picture appears, or mode not supported returns and points to HDMI, cable, or output-format settings next.
Try another HDMI port or cable if needed
If the message remains, reseat or replace the HDMI cable and try a different HDMI port on the TV, then repeat the same power-on order.
You should see: The TV accepts the box signal without the mode not supported message.
Not sure this is the right page? Check here
0 of 5 checked
Extra tips
What to look for: The exact message mode not supported, and whether it appears only on the network box input or on every HDMI source.
Before you change anything: Note which HDMI port and cable are in use. Confirm whether the message appears only with the network TV box. Avoid factory resetting the TV until a power cycle and cable check fail. Never share account passwords or one-time codes with unexpected callers.