Listed below are some common FTP Socket Error Codes:
11001 - Host not found.
Check that the hostname or IP address has been entered correctly.
11004 - Valid name, no data record of requested type.
This error generally indicates that the specified FTP server name is incorrect or not specified. Try entering the hostname or IP address, not a URL (e.g. if ftp://server.domain.com/ is entered, then change it to server.domain.com). Another possibility is that connection is blocked by a firewall. Try temporarily turning off the Windows firewall or any other software firewall you are running.
10061 - Connection refused.
The hostname is correct, but the FTP server is not listening on the port, there is no FTP server running, or a firewall is blocking the connection.
10093 - Connection failed.
This can happen when the network connection goes down, e.g. the FTP server is no longer connected to the network.
10039 - Destination address required.
There may be a problem getting the IP address for the hostname. If you have entered an IP Address, try entering a server and domain name instead (e.g. server.domain.com). Another possibility is that connection is blocked by a firewall. Try temporarily turning off any firewall you are running.
10052 - Network dropped connection on reset.
The host you were connected to crashed and rebooted. Try reconnecting at a later time.
10054 - Connection reset by peer.
Basically, an existing connection was forcibly closed by the remote host. This normally results if the peer application on the remote host is suddenly stopped, the host is rebooted or the remote network was somehow disabled.
10022 - Invalid argument.
Some invalid argument was somehow supplied. In some instances, it also refers to the current state of the socket (e.g. socket is not listening). Also, a firewall running on the host or client machine can be blocking transmission.