My Ethernet connection was working normally about a week ago, but it suddenly stopped. The lights on the PC's built-in Ethernet port no longer turn on. I tested the cable with another device and it works, and both the cable and a new UGREEN USB Ethernet adapter work properly on a laptop and an Xbox. However, neither the motherboard port nor the USB adapter works on this PC.
I've already tried flushing DNS, releasing and renewing the IP address, restarting the PC, switching Ethernet cables, resetting network adapters, rebooting the modem, disabling the proxy, reinstalling both the motherboard LAN and UGREEN adapter drivers, and trying different USB ports. Flushing DNS and renewing the IP briefly restored the connection for around 20 seconds once, but it stopped again and now there are no link lights at all.
What else should I check? Could something on the PC be affecting both the built-in network port and the USB adapter? I do have Proton VPN installed, but it has been on the system for about two years without causing problems.
1 Answer
Since the built-in port and a USB Ethernet adapter both fail on this computer while working with other devices, the cable, router, and adapters are probably fine. The problem is likely something shared by the PC, such as a power state issue or a network filter driver.
Try a complete power drain rather than a normal restart: hold Shift while selecting Shut down to avoid Fast Startup, turn off the power supply if your PC has a switch, unplug it, hold the power button for about 15 seconds, then reconnect everything and boot it again. A network controller can occasionally get stuck in a bad power state, which may keep the link lights off.
After that, you can also run the built-in Network reset from Settings > Network & internet > Advanced network settings > Network reset, then restart the PC. This removes and reinstalls network components and can clear leftover VPN, antivirus, or other filter drivers.
I already tried the network reset, but I’ll try the full power drain. I’ve had Proton VPN installed for around two years without any previous issues, and I don’t remember installing a game-networking tool recently.