Application Specific Password
Generating an application specific password in my ShareFile account resolved this for me and was specifically due to that two-factor was enabled/enforced.
sharefile_client_name/smithjIS@company.com
u3f678ae36
open
command.
ftps
command!
open ftps://username:password@ouraccount.sharefileftp.com
Connecting to ouraccount.sharefileftp.com...
TLS connection established. Waiting for welcome message...
Access denied.
Credentials were not specified.