212 Fortinet Inc.
Configuring L2TP PPTP and L2TP VPN
8Select the Security tab.
9Make sure that Require data encryption is selected.
10 Select the Networking tab.
11 Set VPN server type to Layer-2 Tunneling Protocol (L2TP).
12 Save the changes and continue with the following procedure.
To disable IPSec
1Select the Networking tab.
2Select Internet Protocol (TCP/IP) properties.
3Double-click the Advanced tab.
4Go to the Options tab and select IP security properties.
5Make sure that Do not use IPSEC is selected.
6Select OK and close the connection properties window.
7Use the registry editor (regedit) to locate the following key in the registry:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Rasman\
Parameters
8Add the following registry value to this key:
Value Name: ProhibitIpSec
Data Type: REG_DWORD
Value: 1
9Save the changes and restart the computer for the changes to take effect.
You must add the ProhibitIpSec registry value to each Windows 2000-based
endpoint computer of an L2TP or IPSec connection to prevent the automatic filter for
L2TP and IPSec traffic from being created. When the ProhibitIpSec registry value
is set to 1, your Windows 2000-based computer does not create the automatic filter
that uses CA authentication. Instead, it checks for a local or active directory IPSec
policy.
To connect to the L2TP VPN
1Start the dialup connection that you configured in the previous procedure.
2Enter your L2TP VPN User Name and Password.
3Select Connect.
4In the connect window, enter the User Name and Password that you use to connect to
your dialup network connection.
This user name and password is not the same as your VPN user name and password.
Note: If a RADIUS server is used for authentication do not select Require data encryption.
L2TP encryption is not supported for RADIUS server authentication.
Note: The default Windows 2000 L2TP traffic policy does not allow L2TP traffic without IPSec
encryption. You can disable default behavior by editing the Windows 2000 Registry as
described in the following steps. See the Microsoft documentation for editing the Windows
Registry.