Updated on:
If Ethernet suddenly stopped working, reseat the cable at both ends, try a cable that works on another device, then switch to another LAN port on the router. Change one thing at a time so you can see what fixes it. If your computer still detects the cable but says it has no internet, check whether other devices can get online.
An Ethernet link connects your computer to the next device, usually a router or switch. Internet access also depends on your computer getting a usable network address and the router having a working connection to your provider.
Choose the fix that matches what you see
| What you see | What to check first |
|---|---|
| “Network cable unplugged” or Ethernet shows as disconnected | Reseat the cable, try a working cable and switch LAN ports. |
| Wi-Fi works, but Ethernet says “No internet” | Check the wired adapter and whether it received an IP address. |
| Several devices lose internet at the same time | Check the router, modem or provider outage status. |
| Ethernet drops when you move the cable or wake the computer | Check the plug, wall jack, dock or adapter. Note when it happens. |
1. Test the cable, router port and anything in between
- Reseat both plugs. Push them in until they click. At the router, use a LAN port. The WAN or Internet port usually connects the router to the modem or fiber box.
- Swap only the cable. Use a short cable you have seen work. If the new cable fixes the problem on the same ports, replace the old one. A broken clip, crushed section or sharp kink is a reason to replace an Ethernet cable.
- Swap only the router port. Keep the working cable and try another enabled LAN port. If only one port fails, check that port and its settings.
- Try a direct connection. Where possible, connect to the router without the wall jack, extra switch, dock or powerline adapter in the path. Add those parts back one at a time if the direct connection works.
If another computer works on the same cable and port, focus on the first computer’s adapter or settings. Briefly turn off Wi-Fi on the computer you’re testing so you can tell whether the wired connection works. Do this from the computer itself if you normally access it remotely.
If Ethernet connects but the link is slower than you expect, check whether the cable or port is limiting its speed.
2. Check whether the whole network is offline
Try another device connected to the same router. On a phone, turn off mobile data for the test. If Wi-Fi and Ethernet devices are both offline, check your provider’s outage page and the modem or router’s internet status. If Wi-Fi works and several wired devices fail, look for a switch, uplink cable or router port they share.
To restart a home network with a separate modem and router, disconnect their power, wait about 30 seconds, then power up the modem first. Wait for it to come online before powering up the router. With a combined unit, restart that one device. A normal restart keeps your saved settings. Save the recessed reset button for your provider’s instructions, since a factory reset can erase the setup.
3. Fix Ethernet that connects but has no internet
On Windows, open Settings > Network & internet > Ethernet to check the connection. For more detail, run this in Command Prompt and look for your Ethernet adapter:
ipconfigOn a typical home network, an IPv4 address starting with 169.254. and a blank default gateway usually mean the computer could not get an IPv4 address from DHCP, the service that assigns addresses. Check that the cable leads to the intended network. If several devices on the same network have this symptom, check the router or a switch they share. If this adapter normally gets its address automatically, you can request a new one from an administrator Command Prompt:
ipconfig /renew "Ethernet"Replace Ethernet with the adapter name shown by ipconfig if it differs. On a Mac using DHCP, go to System Settings > Network > your Ethernet service > Details > TCP/IP > Renew DHCP Lease. Check with your administrator before changing a work device or a manually assigned address. See the Windows command reference and Apple’s DHCP instructions.
If the computer has an address and you can reach the router’s local page, try several websites. On Windows, nslookup example.com tests whether your DNS server can look up that name. A failed lookup is a clue to check DNS settings or reachability. If only one site fails, check whether that site opens on another device.
4. Track down random dropouts or a missing adapter
- If it drops when the cable moves, try a working cable and a different port. If it only happens through a wall jack, test a direct cable before replacing the computer’s adapter.
- If it drops after sleep or when docked, see whether reconnecting the dock brings Ethernet back. Try the computer’s built-in port or a supported USB Ethernet adapter directly. Check the manufacturer’s driver or dock firmware for your exact model.
- If one Windows PC still fails on a working cable and port, open Device Manager > Network adapters. Check whether the wired adapter is listed and enabled. If a USB adapter is missing, reconnect it directly to another USB port. For a missing built-in adapter, check for the driver for your exact PC model. If the problem began right after a driver update, check Properties > Driver > Roll Back Driver if available.
Use Windows network reset as a last step for an isolated PC problem. In Windows 11, find it under Settings > Network & internet > Advanced network settings > Network reset. It resets network adapter settings and may require you to set up VPN or virtual networking software again. Follow Microsoft’s Ethernet troubleshooting guide for your version.
Frequently asked questions
Why did my Ethernet randomly stop working?
Check whether the Ethernet status changes to disconnected during the dropout. If it does, start with the cable, port and dock. If the link stays up, check whether other devices also lose internet at that moment.
Why does Wi-Fi work but Ethernet doesn’t?
Working Wi-Fi on the same router points toward the wired path. Try another LAN port and a working cable. If Ethernet connects but stays offline, check the wired adapter’s IP address and gateway.
Can an Ethernet cable be faulty if the link light is on?
Yes. The light shows a link between the ports. A loose or damaged cable can still connect and then drop out or connect at a lower speed. Try a working cable on the same ports to compare.
Why does my computer say Ethernet is connected but there’s no internet?
The computer sees a wired link, but it may lack a usable address or a route through the router. Check the Ethernet adapter’s address and gateway, then see whether other devices can get online.
What does a 169.254 address mean on Ethernet?
On a home network that assigns addresses automatically, it usually means the computer gave itself a local IPv4 address after it failed to get one from DHCP. Check the connection to the router and try renewing the lease.
Why did my Ethernet link drop from 1 Gbps to 100 Mbps?
Check the speed ratings of both ports and any dock or switch in between. If they all support gigabit, try a short working cable directly between the computer and router.