Lately, many users have been searching the Internet for answers to a failed l2tp connection attempt. If you’re trying to figure it out, come to this post. Techquack has researched several effective methods to solve this problem.
About the error associated with a failed L2TP connection attempt.
An l2tp connection is commonly used to encrypt and protect virtual private networks (VPNs) using the Layer 2 tunnel protocol. VPNs can be used to fool the original connection, which helps people hide their location on certain sites to bypass certain security restrictions.
However, many users report that they cannot establish a VPN connection and receive the error message “Attempted l2tp connection failed because the security layer encountered an urgent error during the initial negotiation with the remote computer.”
What is the reason for the “L2TP connection attempt failed” error?
After receiving numerous reports from multiple users, we decided to investigate the issue and develop a set of solutions to fully address it. We also investigated the reasons that lead to the error and listed them as follows.
Protocols disabled: In some cases, the error is triggered when the Microsoft CHAP v2 protocol is disabled in the VPN connection properties. This protocol must be enabled for most VPN connections to work.
PPP settings: The point-to-point protocol must be properly configured before users can attempt to establish a VPN connection. This protocol includes the LCP protocol, and the LCP protocol has other extensions that must be enabled for the connection to work properly.
Now that you have a basic understanding of the nature of the problem, let’s move on to solving it. To avoid conflicts, be sure to implement them in the exact order in which they are presented.
How do I fix the “L2TP connection attempt failed” error?
Resetting the network adapter
- Right-click on Start and select Device Manager.
- Search for network adapters and enlarge the list
- Identify your network adapter, right-click on it and select “Remove”.
- Click on OK
- Restart your computer. The device will be reinstalled and require a default reset.
If this doesn’t fix the Windows 10 VPN 789 error, try the following solution.
Check the certificate
Make sure that the correct certificate is being used on both the client and server sides. If a public key (PSK) is used, make sure that the same PSK is configured on both the client-side and the VPN server machine.
Restore IPSec on your computer
- Right-click Start and select Run.
- Typical Services.
- Find the IKE and AuthIP IPSec encryption modules
- Locate the IPSec political worker
- Check the status. If it is set to Start, click Restart.
- If the Run option is disabled, turn it on.
- Double-click each of them.
- Select the startup type.
- Switch to automatic mode
- Save changes
- Restart your VPN service
If you’ve followed all of the above steps carefully, your VPN should work without any problems because the protocol settings have been reset to defaults. However, if that still doesn’t work, you’ll have to manually set the encryption method on both the server and client sides to make them compatible.
If you have a particular problem with your computer and still get a Windows 10 VPN 789 error after trying one of the above solutions, you can also contact the support or tech support team of your particular VPN provider and provide details for further help.
Frequently Asked Questions
- Pressing Win + R will open the "Run ..." dialog box.
- Right-click on the VPN connection and select Properties.
- In the VPN properties, go to the Security tab and enable the Allow these protocols option.
- Check the Microsoft-CHAP version 2 option and click OK.
- Click the Network icon on the Windows taskbar. A list of available networks and VPNs will appear.
- Click on the VPN connection. Network and Internet VPN settings are displayed.
- Select the VPN connection. Click the Connect button.
- Enter your user name and password.
- Click OK.
The connection drops and returns error 800: "The remote connection could not be established due to failed VPN tunnel attempts. The VPN server might not be available. If this connection tries to use an L2TP/IPsec tunnel, the security settings required for IPsec negotiations may not be properly configured."
By default, L2TP uses IPSec, which requires UDP ports 500 and 4500 and IP ESP 50. If you disable IPSec, Mobile VPN with L2TP requires only UDP port 1701. This type of L2TP configuration should be acceptable in most environments unless the network is configured in an extremely restrictive way.