First check, if a local area connection (LAN) is in the list of connections of your operating system. If not, make sure that a network driver is installed and working. Please contact the manufacturer if you need further support.
The network link should be enabled. To make sure of this, right-click network connection → activate/enabled (if available).
In addition change the settings of the TCP/IP protocol to obtain IP address and DNS server address automatically.
Windows 10 Windows 8 Windows 7
If the operating system is showing that no network cable is connected, a network socket lock could be the reason.