At least one user is selected under ‘Windows File Sharing’ (as shown under ‘Advanced Options’ in the link above).
Selected username and password are being entered in Infuse.
Note: iCloud username/password cannot be used. If you’re using an iCloud ID to log in to your Mac, you will need to set up a new ‘Sharing Only’ user as described here: https://support.apple.com/kb/PH18695