Both VPN variants, L2TP and IPsec, use the same ports (IKE UDP: 500 or UDP: 4500). The VPN IPSec client, therefore, disables the "IKE and AuthIP IPsec Key Generation Modules" service during installation. The Tgblk Starter service is activated and started instead.
For the reciprocal use of L2TP and IPsec, the corresponding services can be manually activated and deactivated via the Control Panel / System and Security / Administration /Services.
KB-00336