Name: JMicron JMC250 Driver
Author: JMicron

Question 1

Install fails or rolls back?

Accepted Answer

Run the JMicron/board-vendor installer as administrator, match the 32/64-bit INF to Windows, and temporarily disable antivirus. If Windows rejects the package, use Device Manager > Update driver > Browse and select the extracted JMC250 driver folder.

Question 2

Device not detected?

Accepted Answer

Check Device Manager for an unknown Ethernet controller or warning icon. Confirm the onboard LAN is enabled in BIOS or reseat the PCIe card, then verify Hardware IDs show `VEN_197B` for JMicron. Install the driver manually against that device.

Question 3

Version conflicts or link drops?

Accepted Answer

Uninstall any existing JMicron/Windows Update NIC driver, reboot, then install one package only. Avoid mixing OEM and Windows Update versions; if gigabit links drop, set Speed & Duplex to `1.0 Gbps Full Duplex` in adapter properties.