You are a desktop support technician for your company. The company uses a VPN server that supports PPTP and L2TP.

A user of a Windows XP Professional portable computer wants to use a VPN to connect to the network over the Internet when she travels. On the user’s computer, you configure a network connection that establishes a VPN connection to the VPN server. You test the connection, and the connection is
established.

Several weeks later, you increase security by configuring the VPN server to support only certificate-based L2TP VPNs. The user reports that she is unable to establish a connection to the VPN server. All other users can connect to the VPN server successfully.

You need to ensure that the user can always establish a VPN connection to the VPN server.

What should you do?

A.
On the user’s computer, change the type of VPN to L2TP VPN on the Networking tab of the VPN connection.

B.
On the user’s computer, select the Use pre-shared key for authentication check box in the IPSec settings of the VPN connection.

C.
Instruct the user to import a recent certificate revocation list (CRL) to her computer.

D.
Ask an administrator to modify the firewall settings to allow L2TP connections.