How to Disconnect from the Network
To disconnect from the network, simply unplug the Ethernet cable from the PC. Poof — the network, and the Internet, is gone. A small warning bubble may appear in the notification area. It’s also your visual clue that the network has connection issues.
The solution to the problem is to reconnect the cable. Check both ends.
Normally, an Ethernet cable shouldn’t become accidentally unplugged. When it does, it means that the cable’s end is broken. Get a replacement.
Reconnecting to the network is simple: Plug the Ethernet cable back into the PC. There’s nothing else you need to do. Windows instantly recognizes the network connection.
Cables can also go bad, in which case the cable may appear to be plugged in but no signal is coming through the cable. In that case, check the lights on the NIC or router. The lights should routinely blink as network traffic is sent and received. When the light isn’t on or turns yellow rather than green, it can indicate a connection problem. Replace the cable.
It is not recommended that you disconnect the PC’s Ethernet cable from the router (or switch). That approach is rather difficult to determine exactly what you’re disconnecting, unless you’re using a different color of Ethernet cable for each PC.
It’s more common to disconnect from a wireless network than from a wired network. The common way to do that on a laptop is simply to shut the laptop’s lid.