Check that a LAN cable is connected to the LAN port of this machine via the network.
Ensure that this machine has an IP address assigned to it. Tap [Utility] - [Device Information], and check that an IP address is displayed.
If no IP address is displayed, you need to set up the network. For details, refer to Here.
Enable scanning using the Web service. Also, configure settings to detect this machine using the Web service, define information of this machine used as a scanner, and specify how to connect to this machine.
How to configure the setting is explained using Web Connection. For details, refer to Here.