Comcast won't let me activated the modem that I purchased brand new from Amazon and used to have active on a Comcast account in another state. They say they own it. I have the box and receipt from the purchase. After a couple of hours talking with various people they admitted that perhaps they had made a mistake, but couldn't fix it as it involved two different 'regions' of their service. They said it might be fixable in a customer service center, but at that point I was disgusted with it and instead bought a new modem.