First, are you on a public connection? If so, open a web browser and see if you need to agree to a usage agreement before using it, if that's not in, do other devices on the network have WiFi working OK? If yes, reboot the computer with the issue, try again. If that does not work, open a command prompt window and type in "ipconfig /flushdns", hit enter, then do "ipconfig /release" hit enter. Then when that finishes do "ipconfig /renew" hit enter. If that does not fix it, reboot the router.