Split Tunnel VPN does not route TCP traffic in Win10

[JamesBuh]

We use an L2TP Split Tunnel VPN terminated at an MX84

We deploy the VPN with a powershell script which adds the VPN and a couple of routes using the Add-VPNConnectionRoute command.

We have used this configuration for several years without problem.

The last several laptops clients we have tried to deploy we have found that they are unable to use the VPN.

On further troubleshooting it appears that only TCP traffic is affected.

The VPN connects fine and we can ping the desired server across the VPN fine (ICMP).

We can also use nslookup to communicate with the servers fine (UDP)

But any TCP connection (File services, odbc connection etc) times out with no response.

If we edit the VPN to be a full tunnel by enabling the "Use default gateway..." option in the VPN adapter and re-connect the connection works fine.

[JamesBuh]

Have managed to identify the issue.

Issue Resolved

In our example the problem was caused by the presence of "Dell Optimizer" software, if the logged in user was NOT a member of the local admins of the particular machine.

In our case we chose to remove the Dell Optimizer software and the problem has been resolved.