Question Computer not connecting to ethernet, doesn't seem to recognize modem ?

[smc1994]

After a blackout a couple of days ago, my computer stopped recognizing that my network card was installed. Last time this happened, a full power cycle of the PC worked, so I gave that a try. This caused my computer to remember that it has a network card installed, but now it can't connect to the router via ethernet. The list of connections reads "unidentified network, no internet"; running ipconfig via Command Prompt displays an IP address starting with "169.254". From what I have read online, this is a placeholder address that the system falls back on if it can't get an IP address from the router somehow, so I am 99% sure the problem is on the router's end and not mine.

Things I have tried with no success:

• power cycling the computer
• power cycling the modem
• resetting the modem
• resetting the computer
• disabling and reenabling ethernet connection
• uninstalling and reinstalling network adapter
• setting the ethernet connection to use fixed IP addresses instead of getting them automatically from DHCP
• "ipconfig /release + ipconfig /renew" in Command Prompt
• "ipconfig /flushdns + ipconfig /registerdns" in Command Prompt
• "netsh int ip reset" in Command Prompt
• "/flushdns" in Command Prompt
• "winsock reset" in Command Prompt
• installing a new version of the network adapter drivers

ipconfig /release and /renew gives an error message saying that "an address has not been associated with the network endpoint." ipconfig /registerdns fails saying "no DNS servers configured for local system."

Computer is self-built. It is the only device connected to this network that cannot connect to the internet.

Router/Modem: unsure, most likely a Frontier FIOS Quantum Gateway G1100 Wireless Wi-Fi Router FiOS-G110
Motherboard: ASRock X570 Phantom Gaming 4
OS version: Windows 10 version 21H1
Ethernet adapter: Intel I211 Gigabit Network Connection 12.18.12.1
ISP: Frontier
Connection type: Ethernet
Connected devices: 2 (this PC and another desktop)

I'm unsure how to check the make and model or ports of my switches, but there are four on the back of my router. Sorry for being tech-illiterate! I believe the network is on a regular server, not an NAS. A WiFi adapter is connected to the computer via USB, but I do not have a wi-fi router. I am using the internal ethernet connection on my motherboard.

DHCP seems to be failing with error 0x79.

Please help. I've tried just about everything and am at the end of my rope.

 

[rgd1101]

is the network port on the back of the pc light up?

 

[smc1994]

is the network port on the back of the pc light up?

There's a single amber light shining inside. Should the whole port be lit up?

 

[rgd1101]

from manual

https://imgur.com/hxtiaRQ

View: https://imgur.com/hxtiaRQ

is that the speed? so there is no link light?

 

[smc1994]

is that the speed? so there is no link light?

Seems to be so. There's only one light, and it's orange.

 

[SkyNetRising]

Things I have tried with no success:

• resetting the modem

What does this mean? What exactly did you do?

Modem is usually provided by ISP (internet service provider).
If it had any ISP specific settings, then resetting would revert it to factory defaults.
Without any knowledge about those ISP specific settings you would not be able to restore it to normal operation.

Contact ISP support.

 

[smc1994]

What does this mean? What exactly did you do?

Modem is usually provided by ISP (internet service provider).
If it had any ISP specific settings, then resetting would revert it to factory defaults.
Without any knowledge about those ISP specific settings you would not be able to restore it to normal operation.

Contact ISP support.

Disconnecting it from the wall, waiting a few seconds, then plugging it back in. I don't think it matters, though, since it didn't work and signs are pointing to it being a hardware failure (the activity light isn't lit up anymore).

 

[SkyNetRising]

Disconnecting it from the wall, waiting a few seconds, then plugging it back in.

That's the same as power cycling (not a reset).

So your pc is not receiving IP address via DHCP.
Possible reasons

1. Router bad;
2. Bad cable from pc to router;
3. Problem with drivers on pc;
4. Ethernet controller bad (pc);

Try with a different cable.
Try with addon PCIE ethernet card (or USB ethernet dongle).
If nothing works, contact ISP support for router/modem replacement.

 

[smc1994]

Update: I realized this morning that the reason the green light on the ethernet cable wasn't on was because I had my ethernet adapter turned off in Network Connections. When I turn it on, the light comes on. Solid green. It's still giving me a 169.254 "IP".

Any idea what's going on?