I have been able to successfully login using psftp.
When connecting with psftp I used the command:
psftp.exe -v "open firstname.lastname@example.org"
I noticed that after the keys were exchanged the program said:
Using username "open username"
This is a problem because actually, the correct user name is "username" not "open username". So, I tried the following:
psftp.exe -v "email@example.com"
Then, after the keys were exchanged the program said:
Using username "username"
I then inserted my password and was given access, connection at last! I suspect, based on the debug messages given in FZ 3, that FZ is issuing an incorrect command. Instead of FZ issuing the command:
open "firstname.lastname@example.org" 22
Perhaps you can eliminate the word "open" from the command, or is this how fzsftp requires the command?
Either way, perhaps this has helped you out. Let me know if you have any more questions.