I had this question after viewing Server Essentials 2016 L2TP VPN
I can connect to Windows Server 2016 Essentials via PPTP after running the Anywhere Access wizard mentioned; however, I cannot connect via L2TP. I checked my Watchguard M400 firewall policy and the ports for L2TP and IPSec are allowing traffic through to the Windows 2016 Server Essentials. Are there other steps that need to be taken to enable L2TP VPN? Some users are trying to connect via iPhone tethering or Mac OS and the VPN connection is failing.