As far as I know, OSX is basically a Unix variant with a grahical frontend. So while you might know your directory paths as Harddiskname:Users:Username:directoryname, I think the underlying operating system still uses the standard Unix notation of /dir1/dir2/dir3.
So the question is in which context DOSBox is interpreting file names? Is there someway you can start a Unix command prompt (a Shell) on you Mac?
Can you use the commands 'cd dirname', 'ls -l' and 'cd ..' to navigate your way to the directory you want to mount?
Can you use the command 'pwd' (print working directory), to see what the OSX/Unix name is?
What happens if you try to mount the directoy from DOSBox using the path given by 'pwd'?
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MiniMax
DOSBox 60 seconds guide | How to ask questions
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