Ethernet Doesn't Have a Valid IP Configuration: Fix It in Windows

Windows Network Diagnostics reports:

Ethernet doesn't have a valid IP configuration

The connection shows as unidentified or with no internet, and nothing reaches the network. This is a DHCP failure — the adapter could not obtain a usable address — and it is usually fixed in a few minutes.

Why This Happens

A DHCP-enabled adapter broadcasts a request for an address when it comes up. If nothing answers, Windows falls back to APIPA and assigns itself an address from 169.254.0.0/16. That address is valid only on the local link, so it can reach nothing, and Windows reports the configuration as invalid.

Confirm the diagnosis first:

ipconfig /all

An IPv4 address beginning 169.254. on the Ethernet adapter confirms DHCP failed. The causes:

• The DHCP request never reached a server — bad cable, dead switch port, a VLAN with no DHCP relay configured.
• The DHCP server had nothing to give — exhausted scope, or the server itself is down.
• A corrupt TCP/IP stack or Winsock catalog on the PC, frequently left behind by uninstalled VPN or security software.
• The DHCP Client service is stopped or disabled.
• A broken or mismatched network adapter driver, often after a Windows update.
• Static configuration left behind that no longer matches the network.

Fix 1: Release and Renew the DHCP Lease

Start here. Open Command Prompt as administrator (right-click Start → Terminal (Admin)):

ipconfig /release
ipconfig /renew

Then confirm:

ipconfig /all

A real address for your network — 192.168.x.x, 10.x.x.x or similar, with a default gateway listed — means you are done. Still 169.254.x.x means the renew found no DHCP server; continue.

Fix 2: Reset the TCP/IP Stack and Winsock

This rebuilds Windows' networking configuration from a clean baseline and fixes the corruption cases. From the same administrative prompt:

ipconfig /flushdns
netsh int ip reset
netsh winsock reset

Reboot. These commands do not take full effect until restart, and skipping the reboot is the usual reason people report they "didn't work".

After the reboot, re-check with ipconfig /all.

Note that netsh winsock reset clears third-party layered service providers. If a VPN client or proxy tool stops working afterwards, reinstall it — that is expected behaviour, not new damage.

Fix 3: Confirm the DHCP Client Service Is Running

If the service is stopped, no amount of renewing will help:

sc query dhcp

STATE should read RUNNING. If not:

sc config dhcp start= auto
net start dhcp

Check the related services too, since a dependency failure produces the same symptom:

Get-Service Dhcp, Dnscache, nsi, Winmgmt | Select-Object Name, Status, StartType

All should be running. If a "debloating" script or a hardening baseline disabled one, re-enabling it at the service level is temporary — the policy that disabled it needs amending too.

Fix 4: Reinstall the Network Adapter Driver

Do this if the problem started after a Windows update, or if the adapter shows warnings in Device Manager.

1. Open Device Manager (devmgmt.msc) and expand Network adapters.
2. Right-click your Ethernet adapter → Uninstall device. Tick Delete the driver software for this device if offered.
3. Restart. Windows reinstalls a driver automatically.
4. If the problem persists, download the current driver from the PC or motherboard manufacturer's support site — Dell, HP, Lenovo, ASUS — rather than a generic driver site, and install that.

Also check power management, which silently breaks adapters on laptops:

1. In Device Manager, open the adapter's Properties → Power Management tab.
2. Clear Allow the computer to turn off this device to save power.

Fix 5: Check the Physical Path

Eliminate the cheap causes, because they are common and cost nothing to test:

• Swap the Ethernet cable. A partially failed cable can negotiate a link while dropping the broadcast frames DHCP needs — the link light lies to you.
• Try a different switch or wall port.
• Check the link speed in the adapter status. A gigabit adapter negotiating 10 Mbps usually indicates a cabling fault.
• Test the same cable and port with another device. If a second machine also fails to get an address, the problem is the network, not this PC.

On a corporate network, a port in the wrong VLAN, or a VLAN with no DHCP relay (ip helper-address) configured, produces exactly this symptom on an otherwise perfect PC. If a second device fails on the same port, hand it to the network team with that evidence.

Fix 6: Prove It With a Temporary Static Address

This is a diagnostic, not a fix. Setting a static address that matches your network will restore connectivity and confirm DHCP is the only broken part:

1. Settings → Network & internet → Ethernet → IP assignment → Edit → Manual.
2. Enable IPv4 and enter an address in your subnet outside the DHCP range, the correct subnet mask, your gateway, and DNS servers.

If everything works on a static address, DHCP is the fault. Set it back to Automatic (DHCP) once you have the answer — leaving hand-assigned addresses scattered around a network causes conflicts that are far harder to diagnose than the original problem.

Verify the Fix

ipconfig /all

Confirm a non-APIPA address, a correct subnet mask, a default gateway and DNS servers. Then test each layer in turn:

ping 192.168.1.1
ping 8.8.8.8
nslookup microsoft.com

Gateway, then internet by IP, then name resolution. If the first two succeed and nslookup fails, the IP problem is solved and you now have a DNS problem — see fixing "The DNS server isn't responding". If instead the resolver answers promptly but insists the name does not exist, that is a different fault with a different fix: browsers show it as DNS_PROBE_FINISHED_NXDOMAIN, and it points at the record or a stale cache rather than at your adapter.

Prevention

• Reserve addresses for machines that must always be reachable, using DHCP reservations rather than hand-set static addresses.
• Keep network adapter drivers current from the hardware vendor, especially after feature updates.
• Disable adapter power management on laptops and docking stations, where it causes intermittent failures that are miserable to diagnose.
• Retire suspect cables rather than returning them to the drawer.
• Monitor DHCP scope utilisation. An exhausted scope produces this error on many machines simultaneously, which is the signature to look for.

Related Guides

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• Fix Wi-Fi "No internet, secured" in Windows
• Fix WSL "Temporary failure in name resolution"