503 : Server on the TLS secure port does not accept the AUTH command
Explanation
The FTP client program connected to an FTP server that is running on the TLS secure port 990. The FTP server assumes that all connections are protected by the TLS security mechanism and that an AUTH command is not needed to initiate a TLS handshake.
System action
FTP continues.
User response
Close the connection to the FTP server and reconnect without sending an AUTH command.
System programmer response
None.