ASUS ExpertBook B5 Intel Core Ultra 7 165U Ethernet Not Working Fix Windows 11

The Ethernet port on your ASUS ExpertBook B5 Intel Core Ultra 7 165U is not working – the network cable is connected but no internet connection appears, or the Ethernet adapter does not show in Device Manager. Realtek Ethernet driver installation and network configuration restore wired connectivity on the ASUS ExpertBook B5.

This guide covers Realtek Ethernet driver installation, IP reset, and network troubleshooting for the ASUS ExpertBook B5 Intel Core Ultra 7 165U in Windows 11.

“ExpertBook B5 Ethernet port not recognized after Windows update. Device Manager showed no Ethernet adapter. ASUS Support had Realtek PCIe Ethernet driver. Installed and wired network worked immediately.” – Shaiful, network engineer from KLCC

Why Ethernet Does Not Work on ASUS ExpertBook B5

The ASUS ExpertBook B5 Ethernet port uses a Realtek PCIe Gigabit Ethernet controller requiring a separate driver from the Realtek WiFi driver. After Windows 11 updates, the Ethernet-specific Realtek driver can be replaced by a generic Microsoft Ethernet driver that may not support the exact PCIe interface used in the ExpertBook B5. Without the Realtek PCIe Ethernet driver, the wired adapter may not appear in Device Manager or shows with an error code preventing network connectivity.

• Realtek PCIe Ethernet driver missing or replaced by generic Microsoft driver after update
• Ethernet cable defective or not fully seated in RJ45 port
• Router DHCP not assigning IP address causing unidentified network despite physical connection
• Ethernet adapter in Device Manager showing error code 10 (device cannot start)

Fix 1 – Install Realtek Ethernet Driver from ASUS Support

Go to asus.com/support, search for ExpertBook B5 with your model number, and download Realtek LAN or PCIe Ethernet driver for Windows 11. Install and restart. After restart, open Device Manager – Network adapters. The Realtek Ethernet controller should appear. Connect the Ethernet cable and check Settings – Network and internet for a wired connection. If the Ethernet connection shows as connected but no internet, proceed to IP reset in the next fix.

Fix 2 – Reset IP Configuration

Open Command Prompt as administrator. Run the following commands in sequence: netsh int ip reset then netsh winsock reset then ipconfig /release then ipconfig /flushdns then ipconfig /renew. Restart. These commands reset the TCP/IP stack and request a fresh DHCP lease from the router. An Ethernet connection that shows as connected but displays unidentified network or no internet is typically an IP addressing failure that these commands resolve without reinstalling any drivers on the ExpertBook B5.

Test with Different Cable and Port

Try a different Ethernet cable between the ExpertBook B5 and router or switch. Also try a different port on the router or switch. Ethernet cables can fail intermittently – the copper wires inside break while the outer jacket remains intact, causing unreliable connection that appears as no network even though the cable looks fine. A working cable and confirmed router port eliminate physical infrastructure as the cause before further driver investigation.

Fix 3 – Check Device Manager for Ethernet Errors

Open Device Manager – Network adapters. If Realtek Ethernet shows error code 10 (device cannot start), right-click and Uninstall device. Check Delete the driver software. Restart. Install the ASUS-qualified Realtek PCIe Ethernet driver from ASUS Support. Error code 10 on a network adapter indicates the driver failed to initialize the hardware during boot, often due to a corrupted driver installation that requires complete removal before clean reinstallation resolves the startup failure.

Fix 4 – Update ASUS ExpertBook B5 BIOS

Check ASUS Support for BIOS updates for the ExpertBook B5 Intel Core Ultra 7 165U. BIOS updates include PCIe device initialization improvements that can affect Ethernet controller enumeration during POST. An updated BIOS with improved PCIe power-on initialization ensures the Realtek Ethernet PCIe controller is fully initialized before Windows driver loading begins, preventing the race condition where the driver attempts to start before the hardware is ready – a cause of intermittent Ethernet error code 10 on startup.

Frequently Asked Questions

Why is Ethernet not working on ASUS ExpertBook B5 Intel Core Ultra 7?

Realtek PCIe Ethernet driver missing. Install from ASUS Support for ExpertBook B5. Not the same as WiFi driver – Ethernet requires its own separate driver package.

How do I fix Ethernet port on ASUS ExpertBook B5?

Realtek Ethernet driver from ASUS Support, IP reset commands in Command Prompt as administrator, test with different cable, Device Manager error code 10 uninstall and reinstall.

Does ASUS ExpertBook B5 Intel Core Ultra 7 165U have Ethernet?

Yes – built-in RJ45 Gigabit Ethernet port for wired enterprise network connectivity at 1Gbps.

Why does ASUS ExpertBook B5 Ethernet show unidentified network?

DHCP not assigning IP address. Run netsh int ip reset and ipconfig /renew in Command Prompt as administrator to request new IP lease.

Conclusion

ASUS ExpertBook B5 Intel Core Ultra 7 165U Ethernet not working in Windows 11 is resolved by installing the Realtek PCIe Ethernet driver from ASUS Support. IP configuration reset commands restore DHCP connectivity for connections showing unidentified network status. Device Manager error code 10 requires uninstall and clean Realtek driver reinstallation. BIOS update improves PCIe Ethernet controller initialization timing to prevent intermittent startup failures of the Realtek Ethernet adapter on the ExpertBook B5 platform.