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Ordered a refurbished unit from Woot. Shipping was on time and the modem came in a nice box indicating certified refurbished. However, when I tried to activate the modem on Comcast via phone, the rep indicated that the MAC address was already registered on someone else's account and there was no way to activate it on my account. Comcast rep tried to insinuate that the modem could be stolen, but I doubt that. I suppose this is one of the potential drawbacks of purchasing a refurbished product; if it has a history on your ISP and was not properly removed from its previous account you will be out of luck as I am. In summary product could not be activated.