If you followed the perfect server guide when setting up your ISPConfig website like I did, and you’re using Ubuntu, then there’s a good chance your FTP server is not configured properly.
The problem was a “connection refused” status no matter which account I used and regardless of what the permissions were set to (yes, I know that’s bad grammar – I’m giving you free help here, go with it). I had exhausted Google and tried many different fixes before coming to this. Unfortunately, the Ubuntu forums were full of admins that literally had more time to correct the formatting in my posts than to offer any sort of relevant help.
Here’s what worked for me: edit the following config file in your preferred text editor (such as Nano).
nano /etc/pure-ftpd/db/mysql.conf
I changed the line
MySQLServer 127.0.0.1
to
MySQLServer localhost
Then
Restart pure-ftpd