Can't make USB hard drive visible for file transfer

[Serverus Adminicus]

Ok, so I've connected an external hard drive (4TB, exFAT) to my server via USB.  It is recognized via Unassigned Devices.  It's mounted (cd mnt/disks/).  Everything seems good.  I can see the drive via MC and UnRaid's GUI file browser.

I want to transfer about 3.3 TB of data from my array onto this external drive.  

I have tried Filezilla and Krusader and neither are able to "see" the external drive as a destination to copy files to.  

Is there a setting in the external drive I should have clicked to make the drive visible?  Something I should have set up when I installed Filezilla or Krusader as dockers?  

 

I feel really dumb here; can someone walk me through how best to set up this file transfer?  It's big, and I'm squeamish about using MC because I don't know a way for me to log in later and see the transfer's progress.  

[Hoopster]

37 minutes ago, Serverus said:

Is there a setting in the external drive I should have clicked to make the drive visible?

In the settings for the drive in Unassigned Devices, did you enable sharing?

 

[Serverus Adminicus]

Well, now I did.  🙄

 

Thank you - I knew the solution was staring me in the face somewhere.