The USB HDD device cannot be registered.

Select within the text to jump to the related settings screen.

Check if the USB HDD device is connected to the USB port (blue) indicated as “HDD REC”.
If the USB HDD device is properly connected to the blue USB port, register it for recording again because it is already registered as a device for purposes other than recording (such as storage).

Note

If there are devices connected to the USB1 and USB2 ports (only models with three USB ports), temporarily remove them while registering the USB HDD.

Press the (Quick Settings) button on the remote control, then select [Settings] — [System] — [Storage].
From [Device storage], select the USB HDD device you want to register for recording.
Select [Delete and format as removable storage], and then select [Format].
Select [Register for recording].
Follow the on-screen instructions to register the USB HDD device to the TV.

Use [HDD performance check] to verify whether if the USB HDD device specifications meet the requirements.
To perform an [HDD performance check], press the (Quick Settings) button on the remote control, and then select [Settings] — [Channels & Inputs] — [Recording device setup] — [HDD performance check].