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Modem Upgraded/Changed ---now no internet

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Modem Upgraded/Changed ---now no internet

I upgraded my modem. How to I get the new modem to work when I plug it in place of the old modem.

Frequent Visitor

Re: Modem Upgraded/Changed ---now no internet

I would call comcast and let them know your new modem and that you need it activated or registered with your comcast service. Don't quote me on this but I THINK you can do it manually yourself at I always just call support though. If you did all that already, make sure the modem is on the list of compatible modems for xfinity services.


Re: Modem Upgraded/Changed ---now no internet

Connect it to the coax line and power it up. Let it fully sync up with the system ("DS, "US", and the "Online" lights are steadily lit). Connect a computer to it and open up a browser. You *may* see their "Walled Garden" modem self registration page. If so, follow the screen prompts. Have your mobile telephone number, your Xfinity username and password or the account number and telephone number associated with your Comcast account handy.

If not, try calling 1-855-652-3446. That is their device activation line.

If that doesn't work for you, you can call 1-800-comcast and tell a rep that you would like to have a new modem provisioned for service. Have the RF / CM / HFC MAC address and the serial number of it handy.

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