I trying to setup a VPN Server (and setup a connection with the built-in Windows Client) using the L2TP (Client-to-LAN) protocol. Here 's my network topology:

SERVER SIDE

[INTERNET] -> [PROVIDER MODEM/ROUTER (192.168.0.254 LAN)] -> [TLR600VPN (192.168.0.200 WAN / 192.168.1.1 LAN)] -> [MY DEVICES]

CLIENT SIDE

[MY DEVICE] -> [PROVIDER MODEM/ROUTER (192.168.0.1 LAN)] -> [INTERNET]

I tryed to setup following the manual on this TPLINK step-by-step link (I started by 3.3 step). Settings on the server:

[PROVIDER MODEM/ROUTER (192.168.0.254 LAN)]

Ports 500, 1701 and 4500 fowarded;

[TL-R600VPN]

- NAT > VIRTUAL SERVERS for ports 500, 1701 and 4500, using UDP protocol;

- L2TP server with IPSEC Encryption enabled;

- IP Address Pool:

- System log:

2021-09-23 14:22:38 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:28 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:20 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:16 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:14 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:13 ipsec[6506]: <5> 01912557 WAN1: Phase 2 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:13 ipsec[6506]: <5> 01912555 WAN1: Phase 1 of IKE negotiation succeeded. (Peers=192.168.0.200&lt;-&gt;000.00.00.00)
2021-09-23 14:22:13 ipsec[6506]: <5> 01912552 WAN1: IKE negotiation began in responder mode. (Mode=Main Mode, Peers=192.168.0.200&lt;-&gt;000.00.00.00)

(000.00.00.00 as my hide external client IP)

Anyone can help me?

Thanks.

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UPDATE: On Android as Client, I successfully connected.