If your Roku won't connect to Xfinity modem / wireless router call Comcast Wireless 855-308-9453 and insist they set the modem to Channel 11 and also have them set Mode to 802.11 B/GN. This will save you 8 hourse of h*** like I went through. This worked for me as I am using ARRIS TG862 wireless router at 25Mbps speed. Can't vouch for other routers or speeds. See (esp. CAUTION section) for WPA info.
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