I cannot go online to activate my new internet service because my new cable modem etc. hasn't been activated. When I go online with my old phone-line modem, comcast cannot find my cable modem to activate because it is not connected. When I connect it, I cannot go online. Pretty neat huh?
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 when you call.
Bottom line. It MUST be connected to the coax in order to provision it.
Hello, hassanphepher! Welcome to our community! I'm happy to check your modem and see if there are any activation issues. Please send me a private message and include your full name, the account holder's name as it's listed on the billing statement. Click on my name ComcastElla, then click Send a message.