FTPUser@FTPServer FirewallUser Authentication Command Sequence
The FTP Client uses the following command sequence to make a connection when you have configured Style to FTPUser@FTPServer FirewallUser in the Firewall section of the Security Properties dialog box.
OPEN <Firewall_server>
USER <FTP_username>@<FTP_server> <Firewall_username>
PASS <FTP_server_password>
ACCT <Firewall_password>
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