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jenniferrr's profile

New Member

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26 Messages

Sunday, April 10th, 2022 1:29 PM

Ethernet - Router not assigning IP addresses to some devices.

Hi there, 

I have ATT Fiber, and everything was working fine until two days ago. Now two computers in my home (1 Mac and 1 Windows) will no longer connect via Ethernet and receive the error "Ethernet has a self-assigned IP address and will not be able to connect to the Internet." - both computers will connect wirelessly, but I need them connected via Ethernet for my work. 

Other wired devices to the network work fine, wireless is  the wall jack is working fine, the computers are fine (Contacted support for each after Customer Support told me it was an issue on my computer). 

When I first notified support I was sent a new router, but the problem persists. I asked if they could update router settings, but was told the connection was working fine and the issue was the ports on my computers. Both devices are brand new and working fine. Confirmed this is a router issue with both of my computer manufacturers yesterday. 

Each of the computers are connected via an internet switch, which was installed by the ATT Tech who installed the service. Service wires are about 5 months old as this is a new home. (Just trying to give all the details here) 

Steps taken to troubleshoot: 

New router installed

Renewed DHCP Lease 

Tested Wall Jack 

Tested other ethernet connect devices (working normally) 

Troubleshoot with both windows and mac tech team to verify devices are operating fine. 

*NOTE Computer will connect via Ethernet if manual IP address is entered, but need correct one to work properly 

Can someone tell me what settings in the router need to be adjusted to get these working via ethernet again? 

Accepted Solution

Official Solution

New Member

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26 Messages

1 year ago

Hey all - wanted to send an update. 

I called the company that did all the low-voltage wiring in the house and they came out to check all connections. The interior wall wiring is fine, but one of the connectors went bad in the wall jack. Replaced and all is working again, woohoo! (Also under warranty, bonus!)

Thanks again, everyone, who took the time to try and troubleshoot this issue for me. 

New Member

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10 Messages

1 year ago

Try disconnecting one of the computers. If the other one connects the way you need then it's probably an IP address conflict. The easiest fix is assigning a static IP for one of the computers. Doing that varies with the OS and version so google is your best source for that. 

New Member

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26 Messages

1 year ago

Thank you for the response! I have tried that as well... with no luck unfortunately...but will look into a static IP address for one and see if it helps. 

(edited)

New Member

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10 Messages

1 year ago

I was hoping for an easy resolution. A manual address is the same as static just means you set the address not the router. Typically, routers are set to assign addresses as needed (dynamic). If you set it to use static, then ever device will need to be set manually. What is the manual address you used?

New Member

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26 Messages

1 year ago

Absolutely, me as well, ha! 

The static IP address I used was one from the pool on the ATT router site - it does solve the issue of the “self assigned IP” and the Ethernet connects, but still no net. I assume I’ll have to do more digging to set a DNS server, etc. 

I just don’t understand why it was working great, then stopped…..but I think that is a common question with tech. 

(edited)

New Member

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10 Messages

1 year ago

A software install can cause this problem. I don't think this is an ATT issue. I've run networks and have been near smashing computers over system conflicts, and this still sounds like an addressing issue. It could be one of the other devices you mention. The fact that they are all working suggests that.

New Member

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26 Messages

1 year ago

Would you suggest assigning a static IP address to each device? 

The other hard wired devices are TV's, a WiFi extender, gaming device, home automation hubs, etc. I don't think anything has updated recently. 

The two computers that are having the issues also have not had any new software installed or updates, but you are very correct, that definitely could have an impact.

Community Support

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221.5K Messages

1 year ago

We can help you get assistance to find out why your router isn't assigning IP addresses, jenniferrr.

 

If you still need help after looking into the DNS server, we suggest contacting the team at our paid service, HomeTech. They'll be able to pinpoint the cause of the addresses not being assigned and determine what your next steps should be.

 

If you need help with any other aspect of your service, just let us know. Thank you for visiting the AT&T Community Forums.

 

Aminah, AT&T Community Specialist

New Member

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10 Messages

1 year ago

It's hard to recommend assigning static address without knowing what devices we're talking about. However, trying them one at a time might fix the problem. Just to clarify, if you connect just one computer it connects to both ethernet and internet?

New Member

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10 Messages

1 year ago

One other thought if you're connected wireless on the computers then disable that. It's duplicating the connection and takes bandwidth from other wireless devices.

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