VirtualBox: Windows 10 Guest doesn’t see Shared Folders

Assuming you have a Linux host and Windows guest in VirtualBox and can’t see Shared Folders in your Windows guest, to fix:

  1. in Linux Terminal:

     sudo adduser $(whoami) vboxusers
    
  2. in Virtualbox Windows guest, click Insert Guest Additions in the VirtualBox menu
  3. run setup on the virtual drive that appears.
  4. reboot the Windows guest
  5. from Windows guest Command Prompt

     net use x: \\vboxsvr\share
    

where “share” is the name assigned in the VirtualBox shared folders dialog.