Username@servername Authentication Command Sequence
The FTP Client uses one of the following command sequences to make a connection when you have configured Style to username@servername in the Firewall section of the Security Properties dialog box.
When Passthrough authentication is selected:
OPEN <proxy_server>
USER <firewall_username>
PASS <firewall_password>
USER <username>@<FTP_server>
PASS <FTP_server_password>
When Passthrough authentication is not selected:
OPEN <proxy_server>
USER <username>@<FTP_server>
PASS <FTP_server_password>
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