We have seen erratic behavior with some users who were located behind some
industry standard firewall's with NAT (Network address translation) translation.
The problems can mostly be easily solved by turning on passive (PASSV) FTP
mode in your upload software. This option can be found in pro_FTPD by selecting
"Tools" and then clicking "Options" in the Site Settings window. Please see your FTP
client help for other FTP clients to find the location of this setting. If you still have
problems, and you are behind a firewall, please contact your network administrator.