PPTP on DD-WRT Routers

WARNINGS: 
- if you access your router from WAN and not from LAN, once connected to PPTP you won't be able to reach it. It will be reachable only from LAN. 
- PPTP is an insecure VPN protocol. Don't use it to transfer sensitive data.
- Setting up a WAN connection via PPTP will route all your LAN devices through the VPN. If you want to use the VPN only for some of your LAN PCs/devices, try OpenVPN Client on DD-WRT with Policy Based Routing set. 

Go to Setup > Basic Setup

Connection type: PPTP
Gateway (PPTP Server): hostname of VPN node, such as nl1.vpn.ac
Username: your VPN username
Password: your VPN password
use DHCP: yes or no - this is how your WAN IP address is assigned to the router. In our example we use a fixed IP address, 192.168.1.2
Subnet Mask: 255.255.255.0
Gateway: 192.168.1.1
MPPE Encryption: Enabled
Packet Reordering: Enabled
Connection Strategy: Keep Alive: Redial Period 30 Sec.
Additional PPTP Options: mppe required,no40,no56,stateless

Here is a screenshot with correct settings. 

Save settings and Apply. Give it a minute to connect, then go to Status > WAN to see if connection was successful. Check your IP on a LAN PC visiting http://ip-api.com

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