Pattern to record: The port failed after a storm, PoE incident or cabling event.

Separate the adapter from the network

For motherboard Ethernet, separate the physical link from Windows configuration. Record the board model, link speed and switch-port behaviour; successful Wi-Fi access does not test the wired controller. One possible explanation is that transient energy has shorted or opened protection components near the port.

Link and configuration checks

1. Test a known switch and cable, inspect port magnetics and compare pre-boot and Windows detection.
2. Inspect protection devices and rail resistance before connecting more equipment.

Before internal work

Lightning or surge damage can extend beyond the visible network port. Reconnecting to suspect cabling can damage repaired hardware.

Verify the network path

If the checks support this cause, replace damaged protection and controller components after isolating the fault. Verification should cover cold start, negotiated speed, sustained transfer, restart and wake-on-LAN if used.

For an assessment of your desktop computer, contact AEPC in Burswood or call 027 908 8880. Provide the model and the conditions that reproduce this problem. Workshop visits are by appointment.