This is one of the most frequently asked questions; the asnwer is available in FAQ:
http://www.drivehq.com/ftp/ click on FAQ and Expand All
Please note FTP has 2 modes, Active and Passive. Unfortunately MS command-line FTP client is crippled as it only supports Active, which is almost always blocked by Firewalls. You can use MS command-line FTP client only if you have no firewalls and if your PC has a public Internet IP address.
You can use DriveHQ FileManager 4.0 client, which has a lot of great features and generally much faster than regular FTP client.
You can also use Windows Explorer to access DriveHQ FTP service, just enter the path: