Nikon D780 DSLR Camera (Body Only) - Manual (Page 754)

708 Menu Guide > B The Setup Menu
Reset all settings except [ Language ] and [ Time zone and date ]
to their default values. Copyright information and other user-
generated entries are also reset. Once reset, settings cannot be
restored.
We recommend that you save settings using the [
Save/load
menu settings ] item in the setup menu before performing a
reset.
View the current camera firmware version.
Reset All Settings
G button
U B setup menu
Firmware Version
G button U B setup menu