Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 565)

9.
Select an item.
The options displayed vary depending on the [ Select communication
function ] setting.
Select [ OK ].
10.
Select [New settings].
Select [ OK ].
By selecting [ Select from list ] when communication settings are
already registered on the camera, you can apply the registered
settings.
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