Networks can seem very complicated – and when there’s a problem, it can seem hard to find the answer. Windows includes a helpful Network troubleshooter than can figure out problems and even repair them.
Look out for network errors and notifications
Windows should automatically give you the option of using the Network troubleshooter when it encounters a networking problem, or you can find it from the Start button or by using the options below.
Error messages
If you see a network error message, such as ‘Server not available’ then the message box should include the option to use the Network troubleshooter. Click the words ‘Troubleshoot’ or ‘Diagnose’ in an error messages to run the Network troubleshooter.
Notification area
Right-click the Network icon in the notification area of the taskbar, then choose Troubleshoot problems from the pop-up menu.
Open the Network Troubleshooter
If no error messages are showing, you can still open the Network Troubleshooter manually.
Click the Start button, then click Control Panel. Type troubleshooter into the search box of the Control Panel window. Click Troubleshooting, then choose option Network and Internet.
From the list that appears, click the type of problem that you are experiencing. The Network troubleshooter will attempt to figure out the problem.
Fixing problems with the Network troubleshooter
The good news is that most basic problems, such as your network connection having been accidentally switched off, or your network adapter not waking from sleep, can be fixed by the Network troubleshooter.
If the problem can’t be fixed by the Network troubleshooter, it creates a report – called an ‘event log’ – that details what it found and any technical information. This can be useful if you need to take your computer for repair or call a technical support helpline. To view the event logs:
Click the Start button, then click Control Panel. In the Control Panel window, under System and Security, click Find and fix problems.
Click View history in the left pane. Next, find the event log that you are looking for, then right-click it and click View details. 
This can be used to help further diagnose a more challenging problem with a networking or computer expert