This problem may occur randomly if the following conditions are true:
- You update the routing table of the VPN client.
- When you update the routing table, you configure the scope of the Dynamic Host Configuration Protocol (DHCP) server to use option 249 in the network environment.
When the VPN client connects to the VPN server, the VPN client correctly receives the following addresses:
- Client IP address
- IP address of the Domain Name System (DNS) server
- IP address of the Windows Internet Name Service (WINS) server
However, the DNS Client service first looks for a route that can be used to connect to the DNS server on the VPN adapter. Then, the DNS Client service can determine whether the DNS server on the VPN adapter can be reached.
However, if the DHCP server does not update the client routing table before the DNS Client service validates the DNS server on the VPN adapter, the DNS Client service assumes that the current DNS server on the VPN adapter cannot be reached. Then, the DNS Client service removes the DNS suffix from the VPN adapter on the DNS Suffix Search List. Therefore, the DNS queries are never sent to the DNS server that is present on the VPN adapter, and clients cannot resolve any names on the corporate network.
Method 1Disable Split Tunneling on the VPN adapter. To do this, follow these steps:
- Double-click Control Panel, and then click the Network Connections.
- Right-click the VPN connection that you want to change, and then click Properties.
- Under This connection uses the following items in the Connection Properties dialog box, click Internet Protocol (TCP/IP), and then click Properties.
- Click Advanced, click to select the Use default gateway on remote network check box, and then click OK.
Method 2Turn off the DNS client screening feature. For more information about how to turn off the DNS client screening feature, click the following article number to view the article in the Microsoft Knowledge Base:
Method 3Put the DNS servers on the same subnet as the VPN clients.
Article ID: 942440 - Last Review: Oct 22, 2008 - Revision: 1