A lot of variables are involved when you connect to a network: cables, network adapters, drivers, and routers. So troubleshooting network connection problems can be challenging.
If it's machine with Windows 8.x OS, Microsoft offers 3 tools: Network Troubleshooter, Internet Connections Troubleshooter and Network Adapter Troubleshooter.
FYI: In Windows 8.x you access the troubleshooters by swiping in from the right edge of the screen, tapping Search (or if you're using a mouse, pointing to the upper-right corner of the screen, moving the mouse pointer down, and then clicking Search), entering troubleshooting in the search box, and then tapping or clicking Troubleshooting. Tap or click Network and Internet, and then tap or click Internet Connections.
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