I tried using this modem with Comcast. I entered the mac address and even tried calling D-link to no avail. I wasted a few hours and spent $30 dollars that I wish I wouldn't have wasted. Comcast increased the cable modem fee from $5 a month to $7 a month. That really irritated the hell out of me. That is why I decided to buy my own modem.If you need to buy a modem to save money and you have Comcast - beware! This probably will not work for you. The D-link customer service lady told me that the D-link cable modem, model DCM-202 model does work with Comcast. I don't know if I'm willing to take that risk though.Good luck!