Fix Hyper-V Default Switch Losing Internet Sharing After Reboot
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Fix Hyper-V Default Switch Losing Internet Sharing After Reboot

After you reboot a Windows 11 host running Hyper-V, the Default Switch may stop sharing the host’s internet connection with guest virtual machines. This leaves VMs unable to reach the internet even though the host can connect normally. The root cause is that Windows Networking settings or the Hyper-V Virtual Switch service fail to restore the shared internet connection state after a restart. This article explains why the Default Switch loses internet sharing and provides step-by-step methods to fix it permanently.

Key Takeaways: Restore Hyper-V Default Switch Internet Sharing After Reboot

  • Hyper-V Manager > Virtual Switch Manager > Default Switch > Connection type: Ensure the switch is set to External network and bound to the correct physical adapter.
  • Windows Settings > Network & Internet > Advanced network settings > More network adapter options: Check that Internet Connection Sharing is enabled on the host adapter and pointed to the Hyper-V virtual adapter.
  • Services.msc > Hyper-V Virtual Switch Management: Set this service to Automatic startup to ensure it restores sharing after every reboot.

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Why Hyper-V Default Switch Loses Internet Sharing After Reboot

The Hyper-V Default Switch is a virtual switch that uses Network Address Translation to share the host’s internet connection with guest VMs. After a reboot, Windows may not correctly reapply the Internet Connection Sharing binding between the physical network adapter and the virtual adapter created by Hyper-V. This happens because the Hyper-V Virtual Switch Management service can sometimes start before the host’s network stack is fully initialized. When the service starts early, it fails to bind the sharing correctly, leaving the Default Switch in a broken state.

Another common cause is that the host adapter’s Internet Connection Sharing setting is reset or disabled by Windows Update or third-party networking software. Additionally, if the Default Switch is configured as an Internal switch instead of an External switch, the NAT translation may not work after reboot. Understanding these causes helps you apply the correct fix.

Steps to Fix Hyper-V Default Switch Internet Sharing Permanently

Use the methods below in order. Start with Method 1 because it resolves most cases without additional configuration changes.

Method 1: Reconfigure Internet Connection Sharing Manually

  1. Open Network Connections
    Press Win + R, type ncpa.cpl, and press Enter. This opens the Network Connections window.
  2. Identify the host adapter and the Hyper-V virtual adapter
    Look for the adapter that connects your host to the internet. Typically, this is named Ethernet or Wi-Fi. The Hyper-V virtual adapter is usually named vEthernet (Default Switch).
  3. Disable Internet Connection Sharing on the host adapter
    Right-click the host adapter and select Properties. Switch to the Sharing tab. Uncheck the box labeled Allow other network users to connect through this computer’s Internet connection. Click OK.
  4. Re-enable Internet Connection Sharing on the host adapter
    Right-click the host adapter again and select Properties. Go to the Sharing tab. Check the box Allow other network users to connect through this computer’s Internet connection. In the Home networking connection dropdown, select vEthernet (Default Switch). Click OK.
  5. Restart the Hyper-V Virtual Switch Management service
    Press Win + R, type services.msc, and press Enter. Find Hyper-V Virtual Switch Management. Right-click it and select Restart.
  6. Test the connection from a guest VM
    Open a guest VM in Hyper-V Manager. From inside the VM, open a web browser or run ping 8.8.8.8 in Command Prompt. If the VM reaches the internet, the fix is successful.

Method 2: Set the Hyper-V Virtual Switch Service to Automatic (Delayed Start)

If the sharing still fails after reboot, the service may start too early. Changing its startup type to Automatic (Delayed Start) gives the network stack time to initialize.

  1. Open Services
    Press Win + R, type services.msc, and press Enter.
  2. Locate Hyper-V Virtual Switch Management
    Scroll to find the service named Hyper-V Virtual Switch Management. Double-click it.
  3. Change the startup type
    In the General tab, set Startup type to Automatic (Delayed Start). Click Apply and then OK.
  4. Restart the host
    Restart your Windows 11 machine. After the reboot, verify that guest VMs have internet access.

Method 3: Create a Batch Script to Reapply Sharing on Boot

If the above methods do not work, you can automate the sharing reapplication with a startup script.

  1. Open Notepad
    Press Win + R, type notepad, and press Enter.
  2. Paste the script
    Copy and paste the following commands into Notepad:
    netsh interface ip set address "vEthernet (Default Switch)" dhcp
    netsh interface ip set dns "vEthernet (Default Switch)" dhcp
    net stop "hns" && net start "hns"
  3. Save the file as a batch script
    Click File > Save As. Set Save as type to All Files. Name the file FixHyperVShare.bat. Save it to your Desktop.
  4. Add the script to Task Scheduler
    Press Win + R, type taskschd.msc, and press Enter. In the right panel, click Create Basic Task. Name it Fix Hyper-V Sharing. Set the trigger to When the computer starts. Set the action to Start a program and browse to the FixHyperVShare.bat file. Complete the wizard.
  5. Restart and test
    Restart the host and open a guest VM to confirm internet connectivity.

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If the Default Switch Still Has Issues After the Main Fix

Guest VM Shows No Network After Host Reboot

If individual VMs still lack network access, the VM’s network adapter may be set to the wrong switch. In Hyper-V Manager, right-click the VM and select Settings. Under Hardware, select Network Adapter. Ensure the Virtual switch is set to Default Switch. Click OK and restart the VM.

Internet Connection Sharing Option Is Missing on the Host Adapter

The Sharing tab may be absent if the host adapter is a virtual adapter itself or if a third-party firewall removed it. Open Network Connections, right-click the host adapter, select Properties, and click Install. Select Service, click Add, and choose Internet Connection Sharing from the list. This reinstalls the missing component.

Default Switch Is Set to Internal Instead of External

Open Hyper-V Manager. In the right panel, click Virtual Switch Manager. Select Default Switch. Under Connection type, choose External network and select the correct physical adapter. Check the box Allow management operating system to share this network adapter. Click Apply and OK. Restart the host.

Internet Sharing Methods: Default Switch vs External Switch

Item Default Switch (NAT) External Switch (Bridge)
Description Uses NAT to share host internet with VMs Bridges VMs directly to the physical network
IP addressing VMs get private IPs from Hyper-V (192.168.x.x) VMs get IPs from the local network’s DHCP server
Host network performance Minimal impact May reduce host bandwidth slightly
Reboot stability Frequent loss of sharing after reboot Rarely loses connectivity after reboot
Best for Testing and isolated labs Production or VMs needing LAN access

This article explained why Hyper-V Default Switch loses internet sharing after a reboot and provided three methods to fix it: manual ICS reconfiguration, delayed service start, and an automated startup script. After applying the fix, test the connection from a guest VM using a browser or ping command. For persistent issues, switch to an External Virtual Switch to avoid NAT-related problems altogether. As an advanced tip, you can export and import the Default Switch configuration using PowerShell commands Get-VMSwitch and Set-VMSwitch to quickly restore settings after a major Windows update.

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