Here is the situation. I connect via VNC to a computer running UltraVNC server. Then, I connect to a VPN on the UltraVNC server computer that I 've just connected to. Once the VPN connection is established, the VNC connection to the UltraVNC server is lost, thus ending my VNC session. How can I connect to a VPN from the UltraVNC server computer and not kill the VNC session? All computer are running Windows 7.

  • A VPN connection generally forces all network traffic through the VPN. By connecting to a computer and then initiating a VPN at that computer, you're interrupting your initial connection. Is there any reason you cannot initiate the VPN connection from the initial host? – music2myear May 21 '12 at 17:13

I think you need to untick the Use default gateway on remote network option on the VPN connection.

  1. Edit the VPN connection properties.
  2. Click on the Networking tab.
  3. Click on Internet Protocol Version 4.
    1. You may also need to disable Internet Protocol Version 6
  4. Click the Advanced button.
  5. Untick the Use default gateway on remote network option.
  6. Press OK to apply the new settings.

Advanced TCP/IP Settings


You don't provide much detail around the Virtual Server you are trying to connect to, but I guess you connect via RDP from a client PC Machine M to a server S located on a network N and while connected to M, you setup a VPN connection to Network V. Is that correct?

If yes, the most likely reason why your connection to Server S drops is because your VPN client was configured to prevent Split Tunnel.

Under this sort of configuration the VPN client modifies the normal IP routes so that all traffic leaving the client PC must flow through the VPN tunnel (excluding of course the traffic required to establish the VPN tunnel itself).

As consequence, the session between Machine M and Server S is not routed via the tunnel to VPN Network V and from there redirected to Server S on Network N.

This will generally cause many issues due to one of the following:

  • The traffic routed to the VPN tunnel will suffer NAT before reaching to Network N and as consequence Server S will reject packets as Sequence numbers and other TCP session values on Machine M don't match those on Server S;
  • The router on Network V doen't know or intentionally block the traffic to Network N the connection will simply be dropped.

The good news is: This behaviour is configurable.

The bad news is: Usually the VPN admin restricts the user ability to change this setting on it client configuration.

Hope this helps

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.