Try to factory reset the router by holding the reset button for ten seconds until all lights blink. Then connect a computer to the router via ethernet and open a web browser. Type in 192.168.1.1 if it is a linksys or cisco, 192.168.0.1 if it is a d-link or netgear, or 192.168.2.1 if it is a belkin. Newer routers might have the user id and passoword to access the router located on a sticker on the bottom or the back of the router. If it is the wifi passphrase you need, then go ahead and reset the router to factoy setting. If ther is any nating or other static IP address settings then you might want to consult the manufacturer and/or your ISP.
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Try to factory reset the router by holding the reset button for ten seconds until all lights blink. Then connect a computer to the router via ethernet and open a web browser. Type in 192.168.1.1 if it is a linksys or cisco, 192.168.0.1 if it is a d-link or netgear, or 192.168.2.1 if it is a belkin. Newer routers might have the user id and passoword to access the router located on a sticker on the bottom or the back of the router. If it is the wifi passphrase you need, then go ahead and reset the router to factoy setting. If ther is any nating or other static IP address settings then you might want to consult the manufacturer and/or your ISP.