U

Visitor

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3 Messages

Sunday, April 27th, 2025 2:39 PM

Modem Not Working in other room.

We just moved into a new place and tried to get the internet set up in our office but we’re having trouble. So we decided to set it up in the living room to make sure we were getting service and the equipment worked, and it did! It worked great in the living room. Today I am trying to move it into the office so we can use it on our computers but now the xfinity app is telling me that this modem is not compatible even though it was working amazing in the living room 30 minutes ago. Is anyone able to help? The modem is an Arris CM8200. 

Gold Problem Solver

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26.4K Messages

23 days ago

... The modem is an Arris CM8200. 

Is that a typo? The CM8200 is not included on their recommended/compatible list at the "All Compatible Devices" link near the bottom of https://www.xfinity.com/support/devices (at the moment it points to https://assets.xfinity.com/assets/dotcom/projects/cix-4997_compatible-devices/2025.03.25%20Full%20List%20of%20Compatible%20Devices.pdf, but this changes from time to time).

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.

Contributor

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21 Messages

23 days ago

Not sure why it would work in one room and not the other, but afaik, Xfinity considers the CM8200 to be a rental device and usually blocks them.

Take a look at the CM8200 reviews on amazon for more details.

Official Employee

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3.3K Messages

21 days ago

 

user_7ow1fc Hello and thank you for taking the time to reach out to us here on our Xfinity Forums. If you had initially tried to set up the modem in the office but were unable to activate it, it could be the outlet is not active. @BruceW is right however, that the CM8200 is not included in our supported devices, which is why you are receiving that error. Have you checked out the list of compatible devices he linked in his comment? 

 

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