First, check the network cable to open the Control Panel, select "Networks and the Internet", check "Wlan" or "Ethernet" is connected.
Second, to regain the IP address information after the network cable failure is still unable to connect, you need to see the IP address of this computer, whether properly allocated. Win8.1, press win+x, select command (admin id), enter ipconfig, and view.
If the following conditions occur or the IP address begins with 169, this means that the NIC does not get the correct IP address.
If the user obtains the IP address of the Internet through the DHCP LAN way, can use the ipconfig/release command to release the existing IP address information, ipconfig/renew obtains the suitable IP address from the DHCP. Iii. Diagnostic Network Connections under Win8.1, you can use Windows Network Diagnostics to check out the cause of some problems. Open Control Panel, select Network and Internet, view the properties of "Wlan" or "Ethernet", click "Diagnostics" and go to "Windows Network Diagnostics" for inspection.
If you check for related issues, you can fix them according to the problem you found.
Four, the network card driver too new or too old this needs the user to troubleshoot, drive General to the hardware manufacturer release, and through the Microsoft Certified Network card driver.
V. Network operator problems when the Internet is not available, the reason is part of the operator.