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"Ethernet Doesn't Have a Valid IP Configuration": Fixes

Windows network troubleshooting found that the Ethernet adapter didn't get a usable IP address from the router (DHCP failed).

The Windows troubleshooter reports “Ethernet doesn't have a valid IP configuration” and the wired connection doesn't work.

  • No internet over Ethernet; Wi-Fi may work.
  • `ipconfig` shows a 169.254.x.x address.

Quick fix

Restart the router and the PC. Then, as administrator: ipconfig /release, ipconfig /renew. If the address still starts with 169.254, DHCP isn't answering: try another cable or router port.

Why it happens

Router's DHCP didn't answer (needs restart, pool full).Most likely
Faulty cable, port or adapter.Sometimes
Static IP settings left over from another network.Sometimes
Driver or Windows network stack problem.Sometimes

Fixes

  1. Restart and renew

    1. Restart router and PC; run ipconfig /release and ipconfig /renew.

  2. Set IP to automatic

    1. Settings › Network & internet › Ethernet › IP assignment › Edit: Automatic (DHCP).

  3. Reset the network stack

    1. netsh winsock reset and netsh int ip reset, then restart.

  4. Check hardware

    1. Swap the cable and router port; update or reinstall the Ethernet driver in Device Manager.

  5. On a Mac

    1. The same failure shows as a self-assigned IP address; renew the DHCP lease in System Settings › Network › Ethernet › Details › TCP/IP.

Still not working?

If several devices on the same router can't get addresses, the router's DHCP server is failing; restart or reset it. If only this PC can't, its adapter or driver is the suspect.

See it in the app

On a Mac, LightAtom's connections view shows apps coming back online once the Mac has a valid address.

Frequently asked questions

What does “doesn't have a valid IP configuration” mean?

The adapter has no usable IP address, usually a self-assigned 169.254.x.x address because the router's DHCP didn't respond.

How do I fix it without the troubleshooter?

Restart the router, renew the IP with ipconfig /release and /renew, set IP assignment to automatic, and reset Winsock and TCP/IP.

What is the Mac equivalent?

A self-assigned IP address shown in System Settings › Network. The fixes are similar: renew DHCP, restart the router, recreate the service.

Related

LightAtom team

The people who build LightAtom, a network monitor for macOS.