I'm using a relatively new Windows 11 computer over Ethernet. The connection initially worked normally, but recently Windows began reporting "Connected, no Internet." I temporarily fixed it by reinstalling the network drivers and disconnecting the cable, but the problem returned.
The computer now falls back to Wi‑Fi instead of using Ethernet. Windows' troubleshooter gives inconsistent results: it reports that the default gateway cannot be reached even though I can ping it, then reports a DNS cache problem even though both IP addresses and hostnames resolve correctly. Eventually it says the connection is active but may have poor quality.
I've removed my VPN, disabled proxies and adapter power saving, reinstalled the motherboard manufacturer's network drivers, flushed DNS, renewed the IP address, reset Winsock, restarted the computer, and tested Safe Mode. I've also tried different Ethernet cables, router or switch ports, and manually configured DNS servers such as 8.8.8.8 and 8.8.4.4. Pings, traceroutes, and nslookup work with both hostnames and IP addresses, but applications that require an Internet connection fail over Ethernet. Wi‑Fi works, but it is extremely slow. What else should I test?
3 Answers
If replacing the cable and changing ports does not help, check whether an intervening switch is faulty. An aging or failing switch can allow some traffic, such as ping and DNS, while disrupting normal application connections. Bypassing the switch temporarily or replacing it would help narrow that down.
Test the connection through another router or switch port, including a port that is known to work for another computer. If the issue follows your PC across multiple cables and ports, the built-in Ethernet adapter or its driver becomes the more likely cause. A USB Ethernet adapter is a useful way to confirm that.
Try a completely different Ethernet cable first. A cable can cause intermittent or low-quality connectivity even when basic pings appear to work. If possible, also test the same cable and router port with another computer to isolate the problem.
I tested my roommate’s known-working cable, and it worked normally on her computer but produced the same problem on mine.
I tried several ports, including the one my roommate uses, and the Ethernet connection still fails on my computer.