Check that the Ethernet cable is firmly connected to the correct ports, compare a known-good cable when available, then run Windows' Network and Internet troubleshooter. Use Network reset only after Microsoft's earlier checks because it removes and reinstalls network adapters.
Note whether Windows shows Unidentified network, cable unplugged, no adapter, or no internet. Check router service lights and confirm another device can use the same network before changing the PC.
2
Check both cable connections
Confirm the Ethernet cable is firmly connected to the Windows PC and to the router's Ethernet port, not its Internet port.
3
Compare another cable or port
If available, test a known-good Ethernet cable and a different compatible router port to isolate a physical fault.
4
Run the staged Windows diagnostics
Run the Network and Internet troubleshooter, then follow Microsoft's remaining Ethernet checks in order; leave Network reset until last.
After each cable or port change, wait for the Ethernet status to update and test the router gateway plus a trusted website. Confirm the network is marked with the appropriate public or private profile.
6
Understand limits and consequences
Network reset removes and reinstalls network adapters and can require VPN or virtual-switch setup again. Leave it until Microsoft’s earlier cable, router, troubleshooter, and adapter checks have failed.
7
Use the safest supported follow-up
If a known-good cable and router port work on another computer but not this PC, inspect Device Manager for the exact adapter state and use the PC or adapter maker's supported driver and hardware route.
Video walkthrough
If it does not work
If link lights never appear, compare the cable and port independently and contact the router or PC maker with the results. If link exists but internet does not, follow Microsoft's Ethernet IP and router checks rather than replacing the cable repeatedly.
ⓘ Sources and verification
Checked against official documentation on . Scope: Windows.
Follow the linked first-party guidance if labels differ after a platform or app update.
