OOOMA Won't Connect to AT&T Modem

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Joined: Sun Sep 12, 2010 3:34 am

OOOMA Won't Connect to AT&T Modem

Post by mthomp15 » Sun Sep 12, 2010 3:50 am

I previously had my OOMA connected to my DSL Modem and then wired to my router.... everything worked fine. Last night, the router died (confirmed with manufacturer over the phone... cell phone that is) and I lost all connections. I can wire my computer directly to the modem, and the internet fires right up. However, when i try to configure system in the fashion described in the OOMA manual for a computer without a router, it doesn't connect to the modem (the red lights do not stop blinking on the OOMA box and the Home light on the back does not light up.. the Modem light on the back of the OOMA box does though).

So, I'm not sure what else to do at this point.


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Location: Pennsylvania

Re: OOOMA Won't Connect to AT&T Modem

Post by murphy » Sun Sep 12, 2010 6:06 am

Did you turn off the modem while you were changing what was connected to it?
That is an absolute requirement for all cable modems to make it forget the MAC address of the last device that was connected.
Customer since January 2009
Telo with 2 Handsets, a Linx, and a Safety Phone
Telo2 with 2 Handsets and a Linx

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Location: Northern Indiana

Re: OOOMA Won't Connect to AT&T Modem

Post by WayneDsr » Sun Sep 12, 2010 9:01 am

Make sure you plugged the cable from the modem to MODEM PORT on the back of the Ooma device.
Also make sure you are using a known good cable.
Next connect a pc or laptop to the HOME port of the Ooma device, restart the pc to receive an ip from the Ooma device.
Go to
In the NETWORK menu set up the connection usint PPPoE. Enter in your user name and password for your AT&T Internet account.

Reboot all equipment starting with the DSL modem.

If this still does not work, you may have to connect a pc directly to your AT&T modem and set it to BRIDGE MODE.

ooma customer since January 2009
ooma hardware: core (hub/scout) and Telo
Lifetime Premier Member

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