You will need to check the settings of the router. If you connect the computer directly to the modem, does it work ? If that works then your modem is working properly. Now connect the modem and the computer to the router. open the set up page of the router. Change the settings of the router manually according to the Internet service provider.
Once you have all the proper settings you will be able to go online using the router. Now change the wireless settings of the router. set up your wireless network. on your computer connect to the wireless network.

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