From EZP Knowledge Base

Well, first try the following:

•  Ensure your firewall is not blocking FTP connections.
•  Try FTP'ing directly to the IP address of your site - this info should be in your welcome email you received when you signed up!
•  Ensure your FTP program is using the correct path to connect. Your path should be /home/yourusername/public_html/.
•  Ensure you are using the correct username and password. Your username and password for FTP is the same as you use for cPanel.
•  Try turning on or off Passive mode in your FTP client

If this all fails, submit a support ticket and we will do our best to resolve the problem!