Windows Hamachi Client Fails to Connect to the Hamachi Network Adapter

Symptom

When you launch the Hamachi application, you see a yellow triangle with a "Tunnel problem" error that takes you to an error message that says the following:

network adapter error: Failed to connect to the network adapter. Peer is not accessible via VPN

Cause

hamachi-2.exe was unable to access the Hamachi network adapter.

Resolution One

Make sure the network adapter is enabled in Network Connections, as follows:

Press the Windows key + R.
Result: The Run box is displayed.
Type Control Panel and press Enter.
Result: The Control Panel window is displayed.
Select either Network and Sharing Center or Network and Internet > Network and Sharing Center.
On the left side of the window, click Change Adapter Settings.
Result: Network Connection options are displayed.
Right-click on the Hamachi adapter and select Enable.
Result: A dialog box saying Enabling... is displayed.

Resolution Two

Manually uninstall and reinstall the Network Adapter.

Open the Device Manager, as follows:
1. Press the Windows key + R. The Run box is displayed.
2. Type devmgmt.msc and press Enter.
Result: The Device Manager window is displayed.
Select and delete the Hamachi Virtual Ethernet Adapter, as follows:
1. Click the arrow next toNetwork adapters.
2. Right-click on Hamachi Virtual Ethernet Adapter.
3. Click Uninstall > OK.
Result: The old Hamachi Virtual Ethernet Adapter should now be uninstalled.
Restart the computer.
Using the Hardware Wizard, install the Hamachi Virtual Ethernet Adapter, as follows:
1. Press the Windows key + R. The Run box is displayed.
2. Type hdwwiz and press Enter. The Add Hardware Wizard is displayed.
3. Click Next.
4. Select Install the hardware that I manually select from a list and click Next.
5. Under Common hardware types select Network adapters and click Next.
6. Select Have Disk.... The Install From Disk menu is displayed.
7. Select Browse.... The Locate File menu is displayed.
8. Navigate to the Hamachi installation folder at C:\Program Files (x86)\LogMeIn Hamachi.
9. For Windows Vista, 7, 2008 and 2008R2, select hamachi.inf; for Windows 8 and above, select hamdrv.inf.
10. Click OK > Next.
11. Click Finish.
Result: The Hamachi Virtual Ethernet Adapter should now be installed.
Rename the adapter, as follows:
1. Open Network Connections by pressing Windows key + R and typing Control Panel in the Run box.
2. In the Control Panel window, select either Network and Sharing Center or Network and Internet > Network and Sharing Center.
3. On the left side of the window, click Change Adapter Settings.
4. Right-click on the adapter with the description Hamachi Virtual Ethernet Adapter and select Rename.
5. Rename the adapter Hamachi.
Restart the computer.
Result: The Network Adapter should now be installed and operational.

Resolution Three

Enable the DHCP Client and Network Connections services in services.msc.

Press the Windows key + R.
Result: The Run box is displayed.
Type services.msc and press Enter.
Result: The Services window is displayed.
Locate and right-click the DHCP Client service and select Start.
Result: The DHCP Client service is started.
Locate and right-click the Network Connections service and select Start.
Result: The Network Connections service is started.
Locate and right-click the Hamachi Tunnelling Engine service and select Restart.
Result: The Hamachi software should restart.

Other Resolutions

Disable the firewall on the machine experiencing the error.
Run WinSock to revert certain Windows networking registry values to their defaults. For details, read this Microsoft support article.

Article last updated: 3 October, 2022