L2TP_IPsec Issues

[fmuianga]

Good evening I am Frederico Muianga  recently we made the sale of a firewall Fortigate 800D and we installed it is now with FortiOS 5.6.3,
 so everything is configured with Single Sign On using FSSO software, the problem starts when I try to load an Active Directory user group to allocate to an L2TP IPsec VPN group and authenticate with Active Directory users in the VPN, 
the firewall does not accept gives the following error using the forticlient "VPN connection failed. Please check your configuration, network connection and pre-shared key then retry your connection. If the problem persists, contact your network administrator for help." 
I do not know what might be causing this problem, I ask for help

[ede_pfau]

hi,

and welcome to the forums.

The FortiClient offers IPsec VPN and SSL VPN, not L2TP. You can use the built-in L2TP VPN in Windows if you like but most people would recommend to create an IPsec VPN for remote access. You can use FSSO with both IPsec and SSL VPN.

OK, this can be confusing because in L2TP VPN there's IPsec mentioned as well. The underlying protocol is L2TP but some part of the data is encrypted by IPsec. FortiClient does not support L2TP protocol.

[fmuianga]

Thank you for your help.