問個wireless router連接的問題，謝謝

以前一直用at&t上網，最近剛換到comcast,需要從新setup router.
用了安裝盤後顯示your router has already been set up. You need
to use an easy setup key in order to connect to your router.
請問我要怎樣做啊？電腦盲一個。