I've tested it, and its works, with quotes and no escape character.
yes? use "/Users/marti/My File.nc"
I think the above is the solution.
The confusion arises from (*footnote*)
> /Volumes/WD\ Backup/ . . .
Ferret doesn't (seem to) understand this escape. The only escape Ferret has for spaces is the double quotes.
In contrast, the shell understands both types of escape:
Ryo
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(*footnote*) On the bash prompt, type
$ ls /Volumes/WD (hit the tab key here)
Then, you'll get /Volumes/WD\ Backup/ . . . On the other hand, type
$ ls "/Volume/WD (hit the tab key here)
Then, you'll get "/Volumes/WD Backup/ . . . "