Power cycling your Modem and Router might help:
1. Save all your current work close all open applications then shut down your computer. Wait for a minute.
2. First turn your Router off and wait for a couple of minutes.
3. Turn off your modem.
4. Disconnect all the ethernet cables that are connected to the router and modem and the PC.
5. Reconnect them and ensure that there are no loose connections in between them.
6. Now switch on your PC and let it boot.
7. Switch on the modem first and after it gets initialized switch on the router.
Unplug the router. Wait ten seconds. Turn it back on. If that doesn't fix the issue there should be a button that resets the router to factory defaults.You will have to hold it for about ten seconds as well. I don't recommend doing this if don't know how to set up a router. Definitely don't do if the router was provided and set up by your Internet Service Provider.
If it was they might have a Username and Password in the Router User Interface that will have to be entered. If it does and you know the Username and Password and know how to setup the router than be my guest. There is also a chance that the network isn't being broadcasted or the SSID is hidden. If that's the case just go to UI and enable broadcasting or change the SSID to broadcast. Good luck!
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