Visitor

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3 Messages

Thursday, November 6th, 2025 6:51 AM

Xfinity app won't let me deregister old modem and register new one

Bought a new modem and want to replace the one currently registered to my account. Second modem is Netgear nighthawk and first one is Arris (not Xfinity). The app won't let me register a new modem, which I think has something to do with the Arris still being on there. It won't let me remove the Arris one. Xfinity says there's an outage, but the "register with Xfinity app" captive portal page seems to load fine on the router . Can a technician manually remove my original modem and register my new one? 

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Official Employee

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472 Messages

1 month ago

Good morning @user_f584mw, and thanks for reaching out to us on the Xfinity forums, I hope this message finds you well. I am sorry to hear about the issues you are having adding the new modem to the account. You should not have to remove an old modem before you can add a new one on. When you go into the app and select the option that says got new equipment to set up, is that where you are getting the error?

Visitor

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3 Messages

It when I click to set up a new modem, it says the cm mac is invalid, despite being exactly what's printed on the box and router and what's displayed in the router software. But it keeps asking me to scan something like its expecting an Xfinity router, even though I clicked set up my own equipment. Can someone at Xfinity manually input my new cm Mac address in? I am not able to call at the moment. 

Visitor

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3 Messages

1 month ago

Update: it was making me scan a code like it was expecting an Xfinity modem. Once I chatted with Xfinity to remove my previous modem, it let me set up my Netgear modem. Note that I clicked to set up third party equipment both times, the only difference is the second time I had an agent manually deregister my first modem. . I'm guessing it's a bug with the Xfinity app. But after I got the other modem manually removed, I was able to click the button for third party (not Xfinity) equipment and it showed me new options and accepted the same exact mac (without saying "unrecognized" and falling). I'm having other problems with speed and network dropping but that was happening with all three modems so I guess it's a connection issue. I'll have to talk in the chat again. 

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