Troubleshooting L2TP VPN Connection Issue on Windows 10

If you’re experiencing difficulties connecting to an L2TP VPN (Layer 2 Tunneling Protocol) on Windows 10, there are a few troubleshooting steps you can follow. This guide will walk you through the process of adding a registry key and ensuring the necessary protocols are allowed to establish a successful L2TP VPN connection.

Adding the Registry Key

To begin, you’ll need to add a registry key that can help resolve L2TP VPN connectivity issues. Follow the steps below:

1. Press Windows + R on your keyboard to open the Run dialog box.

2. Type regedit and hit Enter to open the Registry Editor.

3. In the left-hand pane of the Registry Editor, navigate to the following key:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\PolicyAgent

4. Right-click on the PolicyAgent folder, select New, and then choose DWORD (32-bit) Value.

5. Rename the newly created DWORD value to AssumeUDPEncapsulationContextOnSendRule.

6. Double-click on the AssumeUDPEncapsulationContextOnSendRule value and set its Value data to 2.

7. Click OK to save the changes.

Allowing the Necessary Protocols

In addition to the registry key, it’s important to ensure that the required protocols are allowed in order to establish an L2TP VPN connection on Windows 10. Here’s how you can check and enable the necessary protocols:

1. Press Windows + X on your keyboard to open the Power User menu, then select Network Connections from the list.
2. In the Network Connections window, locate the VPN connection you’re trying to establish.
3. Right-click on the VPN connection and choose Properties.
4. In the Properties window, select the Security tab.
5. Under the Security tab, click on the Allow these protocols checkbox.
6. Make sure the following protocols are selected:
   • Challenge Handshake Authentication Protocol (CHAP)
   • Microsoft CHAP version 2 (MS-CHAP v2)
7. Click OK to save the changes.

Once you have completed these steps, try connecting to your L2TP VPN again. The changes you made to the registry key and the enabled protocols should help resolve the connectivity issues on Windows 10.

Remember to restart your computer after making any registry modifications to ensure the changes take effect properly.

Hopefully, this guide has helped you troubleshoot and resolve your L2TP VPN connection issue on Windows 10. If the problem persists, you may want to contact your VPN provider for further assistance or consult Windows support resources for additional troubleshooting steps.