If your iPhone or iPad pops up the message "Connection Refused" this could be because of one of two things:
Macs:
1... You have not turned FTP on. Click here to learn how.
PC:
1... You have not installed an FTP server. Click here to learn how.
2... Your Firewall is stopping incoming connections from your iPhone. This is a feature of your computer to help protect you against internet hackers. Click here to learn how to check this.