OK,
Here is the background...
Server2102R2 Datacenter as host
Server2012R2 standard as Hyper-V VPN server
WIndows10Pro build 2004
Comcast business as Primary ISP
HughesNet as secondary ISP
Current Comcast ISP modem is theirs
I had this working for several years until I upgraded Comcast business to their modem from an Arris (easier for them to fault isolate)
I have several laptops and MS Surface WIndow10 Pro systems. Before the Modem swap out, all connected remotely.
Now only one Laptop (ThinkPad W510) will connect through to VPN server.
VPN server configuration is all green
My test is to WiFi the laptop to the HughesNet ISP that is not part of the LAN. That is how the ThinkPad W510 connects as part of this test and is shown on the VPN connected clients status page.
When I try a laptop or surface pro, I get the following through HugheNet ISP...
The network connection between your computer and the VPN server could not be established because the remote server is not responding.
VPN protocol...
L2TP with pre-share key
Key is correct
Address is remote.mydomain.com
VPN adapters are configured the very same way as the ThinkPad W510 which works ( and they did in the past).
To test, I changed the VPN server name to 192.168.x.x which is the LAN IP address of the VPN server. Both laptop and surface pro connect through the router to the VPN and all 3 systems appear in the VPN client connection page.
The router ports are correctly forwarded to VPN server both LAN and WAN (through the comcast modem)
So my question is why only the ThinkPad W510 connecting through the Comcast Modem when all did through the Arris with the same router and VPN server configuration?