How to Fix Ethernet Connection Problems on Your Computer

2026-10-14 · LC Repair

Your Ethernet cable is plugged in but you have no internet. The network icon in the taskbar shows a disconnected status or displays Unidentified Network. Or the connection works intermittently, dropping and reconnecting. Ethernet connections are normally more reliable than Wi-Fi, so when they fail the cause is usually a cable issue, a driver problem, an IP configuration error, or a disabled adapter rather than a complex networking problem.

Check the physical connection

• Verify the Ethernet cable is firmly plugged in at both ends — the computer and the router or switch. Push the connector in until you hear or feel a click. A partially seated connector makes intermittent contact and causes connection drops
• Check the link lights on both the computer Ethernet port and the router port. When a working connection exists, both ends show a solid or blinking light (usually green or amber). If there is no light on either end, the cable or one of the ports may be faulty
• Try a different Ethernet cable. Cables can be damaged internally without visible signs, especially if they have been bent sharply, pinched by furniture, or chewed by pets. A different cable eliminates this variable quickly
• Try a different port on the router or switch. A single dead port on a router does not affect the other ports. If the new port works, the original port is faulty

Check the network adapter status

• Open Settings, Network and Internet. Look at the Ethernet section. If it says Not Connected even though the cable is plugged in, Windows is not detecting a link
• Open Device Manager and expand Network Adapters. Find your Ethernet adapter (typically labeled Realtek, Intel, or Killer Ethernet). If it has a down arrow icon, it is disabled. Right-click and select Enable Device
• If the adapter shows a yellow warning triangle, the driver has a problem. Right-click and select Update Driver or Uninstall Device, then restart the computer to reinstall the driver automatically
• If no Ethernet adapter appears in Device Manager at all, the network hardware may have failed or been disabled in the BIOS. Check BIOS settings for a LAN or Onboard Ethernet option and make sure it is enabled

Reset the network adapter

• Disabling and re-enabling the adapter forces it to reinitialize the connection. In Device Manager, right-click the Ethernet adapter, select Disable Device, wait a few seconds, then right-click again and select Enable Device
• For a more thorough reset, open Settings, Network and Internet, Advanced Network Settings, and click Network Reset (at the bottom on Windows 11) or use the same option on Windows 10. This removes all network adapters and reinstalls them with default settings. You will need to reconnect and reconfigure any custom settings afterward
• After a network reset, restart the computer. The reset takes effect after the restart

Update or reinstall the Ethernet driver

• Driver problems are the most common software cause of Ethernet failures, especially after Windows updates that can replace working drivers with incompatible generic ones
• Open Device Manager, right-click the Ethernet adapter, and select Update Driver. Choose Search Automatically. If Windows finds a newer driver, install it and restart
• If the automatic search does not help, go to the computer or motherboard manufacturer website and download the latest Ethernet driver for your specific model. Intel, Realtek, and Killer each have driver download pages on their own websites as well
• To completely reinstall the driver, uninstall the adapter from Device Manager (check Delete the Driver Software when prompted), restart, and let Windows detect and install the adapter again. If Windows installs a generic driver that does not work, manually install the manufacturer driver you downloaded

Fix IP configuration

Release and renew the IP address

• If the adapter shows a connection but the network status says No Internet or Unidentified Network, the computer may not have received a valid IP address from the router
• Open Command Prompt as Administrator. Run the commands to release the current IP address and then request a new one from the router DHCP server. This forces the computer to get a fresh network configuration
• If the release and renew cycle results in an IP address starting with 169.254, the computer is not reaching the DHCP server. This means the cable connection to the router is not working (even if the link light is on), the router DHCP service is not running, or there is a device between the computer and router that is blocking DHCP

Reset TCP/IP and Winsock

• Corrupted network stack settings can prevent Ethernet from working even when the physical connection and driver are fine. Resetting the TCP/IP stack and Winsock catalog clears these settings
• Open Command Prompt as Administrator and run the commands to reset the TCP/IP configuration, reset the Winsock catalog, and flush the DNS cache. Restart the computer after running these commands
• This is a safe operation that restores network settings to defaults. Custom static IP configurations, DNS settings, and proxy settings will be cleared, so note them before resetting if you have custom configurations

Check for IP address conflicts

• If two devices on the same network have the same IP address, both experience intermittent connectivity problems. Windows may show an IP address conflict warning in a notification
• The fix is to ensure the computer uses DHCP (automatic IP assignment) rather than a static IP, or to assign a static IP that is outside the router DHCP range and not used by any other device
• To switch to DHCP, open Settings, Network and Internet, Ethernet, and set IP Assignment to Automatic (DHCP). If you need a static IP, use an address above the DHCP range (check your router settings for the DHCP range)

Disable and re-enable energy management

• Windows can put the Ethernet adapter to sleep to save power, which can cause the connection to drop and not recover properly. This is common on laptops
• In Device Manager, right-click the Ethernet adapter, select Properties, go to the Power Management tab, and uncheck Allow the Computer to Turn Off This Device to Save Power
• Some Ethernet adapters also have Energy Efficient Ethernet (EEE) or Green Ethernet settings on the Advanced tab in Device Manager. These power-saving features can cause connection instability with certain routers or switches. Try disabling them if you experience intermittent drops

Check the router and modem

• If no devices on the network have internet (check from a phone on Wi-Fi), the problem is the router or the internet service, not the computer Ethernet connection
• Restart the router and modem by unplugging them from power, waiting 30 seconds, plugging the modem in first, waiting for it to fully connect (all status lights normal), then plugging in the router. This clears the router state and forces it to re-establish the internet connection
• If other devices work fine but only the computer Ethernet does not, the problem is between the computer and the router — the cable, the computer port, the driver, or the router port for that specific connection

Firewall and security software

• Overly aggressive firewall or security software can block network traffic on the Ethernet adapter. If you recently installed or updated security software and the Ethernet connection stopped working, the security software may be the cause
• Temporarily disable the firewall (including Windows Firewall) to test. If Ethernet works with the firewall disabled, add appropriate exceptions or adjust the firewall rules. Remember to re-enable the firewall after testing
• VPN software can also interfere with Ethernet connections by creating virtual network adapters that take priority over the physical adapter. If a VPN is installed, disconnect it and check if Ethernet works without it

Ethernet speed and duplex settings

• If Ethernet connects but at very slow speeds, the adapter may be negotiating at the wrong speed or duplex setting. Normally this is automatic, but mismatches can occur
• In Device Manager, right-click the Ethernet adapter, select Properties, go to the Advanced tab, and find Speed and Duplex. The default is Auto Negotiation, which should work. If speeds are wrong, try manually setting it to match the router port capability (typically 1.0 Gbps Full Duplex for modern hardware)

Need help with Ethernet problems?

If your Ethernet connection is not working and the troubleshooting steps above have not resolved it, LuxuriousComputers Repair can diagnose wired network connection problems, replace faulty cables or network hardware, install proper drivers, and configure your network settings for a reliable Ethernet connection.