The Host name field should contain the name of the computer that acts as the server and has the ActiveCheck™ Service installed and running. (If it is running on the same machine as the client it will be "localhost".) The Communication protocol field allows you to choose between Tcp and Http as the protocol to connect to the server, this setting should be the same as what is set for the ActiveCheck™ Server. The Port setting tells the client which Port to send requests to and, as with the communication protocol, must be set to the same setting as the ActiveCheck™ Server.