How to Solve RTL8111H-CG No Link Detected Problem

How to Solve RTL8111H-CG No Link Detected Problem: Troubleshooting and Solutions

If you're encountering the "No Link Detected" problem with your RTL8111H-CG Ethernet adapter, it indicates that your computer's network interface is not able to establish a connection with the network. This issue could be caused by several factors, including hardware issues, driver problems, or network configuration issues. Here's a step-by-step guide to troubleshoot and resolve the problem.

1. Check the Physical Connections

Before diving into software and settings, ensure that everything physically connected to your computer is in working condition:

Ethernet Cable: Make sure the cable is not damaged and is securely plugged into both your computer and the router or switch. Try using a different Ethernet cable to rule out cable issues. Router/Switch Port: Ensure the port on the router or switch where your computer is connected is functioning correctly. Try plugging into a different port to eliminate the possibility of a faulty port.

2. Verify Network Adapter Status

Make sure your RTL8111H-CG Ethernet adapter is enabled and working correctly in your computer's system:

Open Device Manager (Windows): Press Win + X, then select Device Manager. Locate the Network Adapter: Find the "Network Adapters" section and look for "Realtek RTL8111H-CG". If you see a yellow warning triangle or an error message, the adapter may have a problem. Check the Status: Right-click on the adapter and select "Properties". Under the "Device Status" tab, check for any error messages. If there is an error, you may need to reinstall the driver.

3. Update or Reinstall the Network Driver

Outdated or corrupted drivers are common causes of network connection problems. Follow these steps to update or reinstall your RTL8111H-CG network adapter driver:

Update Driver: Right-click on the RTL8111H-CG network adapter in Device Manager. Select Update Driver. Choose "Search automatically for updated driver software" and follow the prompts. Reinstall Driver: Right-click on the network adapter and select Uninstall device. Restart your computer. Windows should automatically reinstall the correct driver. Alternatively, you can download the latest driver from Realtek’s official website and manually install it.

4. Check Network Settings

Network settings can sometimes interfere with the connection. Make sure everything is configured properly:

Check IP Configuration: Open Command Prompt (type cmd in the search box) and run the command ipconfig /all. Verify that your Ethernet adapter has a valid IP address assigned (not 169.x.x.x, which indicates no connection). Disable and Enable the Network Adapter: Open Network and Sharing Center. Click on Change adapter settings. Right-click the Ethernet adapter and select Disable, then after a few seconds, right-click and select Enable again.

5. Reset TCP/IP Stack

A corrupt TCP/IP stack can cause connection issues. To reset it, follow these steps:

Open Command Prompt as Administrator (right-click on Command Prompt and select Run as administrator). Type the following command and press Enter: netsh int ip reset Restart your computer.

6. Check for Hardware Issues

If the above solutions don't work, there may be a hardware issue with the RTL8111H-CG network adapter. You can:

Test the Adapter in Another Computer: If possible, test the adapter in another computer to see if it works. If it doesn’t, the adapter might be faulty and needs replacement. Try a Different Network Adapter: If you have a USB Ethernet adapter available, try using that to confirm whether the issue lies with the onboard RTL8111H-CG adapter.

7. BIOS and Firmware Update

In some cases, an outdated BIOS or firmware version might cause compatibility issues with the network adapter:

Update BIOS: Check your motherboard manufacturer's website for any BIOS updates related to network adapters. Update Firmware: Some network cards have firmware updates. Check if Realtek provides any updates for the RTL8111H-CG model.

8. Check Router/Switch Configuration

Finally, ensure that your network hardware is configured properly:

Check Router Settings: If you’re using a managed switch or router, ensure that the correct VLANs or network settings are configured. Test with Another Device: If other devices are working fine on the same network, the issue is likely with your computer’s configuration rather than the router.

Summary of Solutions:

Check physical connections (Ethernet cable, router/switch port). Verify the network adapter status in Device Manager. Update or reinstall the network driver. Ensure proper network settings (IP configuration, enabling/disabling the adapter). Reset the TCP/IP stack using the command netsh int ip reset. Test for hardware issues by trying the adapter in another computer or using a different adapter. Update BIOS or firmware if needed. Check router or switch settings for proper configuration.

By following these steps, you should be able to troubleshoot and resolve the "No Link Detected" issue with your RTL8111H-CG Ethernet adapter. If none of these solutions work, it may be time to contact customer support or consider replacing the network adapter.