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PPTP VPN not working after router change

We changed our Internet connection and I'm having trouble configuring the port forwarding on the new router.

Previously we had a basic modem and a Linksys router configured to handle the port forwarding.

Now we are trying to use the ISP provided modem/router Sagemcom 2864 device.

My DC handles the RRAS function as well and has an IP address of 10.10.0.2

An ipconfig reveals that there is a PPP adapter at 10.10.0.60 with a mask of 255.255.255.255

I did not do the initial config of the network here, so I don't know all the details.

On the ISP provided device, I have configured the following port forwarding rule:

Name: VPN_PPTP
Protocol: TCP
Source Port: 1723
Destination IP: 10.10.0.2
Destination Port: 1723

I used canyouseeme.org to verify that the port is visible. When users try to connect however, the Windows VPN connection sits at "Verifying user name and password..." and then fails with error 806 saying the most common cause is that the router is not configured to allow GRE.

How can I fix this?

Thanks!
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Rick_O_Shay
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If you router doesn't support GRE or IP, then try a TCP forwarding for port 47
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ASKER

I tried forwarding for port 47 already. The ISP claims the device supports VPN pass through, but they won't give me any support regarding it.

I gave up and just installed my own router, putting theirs in bridge mode.

Thanks for the responses anyway.
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blitzzkreeg

In response to chakko's comment, forwarding Port 47 won't accomplish anything here, as it has nothing to do with the issue. GRE protocol 47 is well a protocol not an actual port. Port 47 is NI-FTP and thus unrelated to VPN.

VPN Pass-through, if supported by router, will enable the secured traffic quite nicely given the right port is forwarded & an exception on server firewall (if present) is implemented.

Usual VPN forwarded ports, given choice of protocol are PPTP Port 1723 TCP, L2TP Port 1701 UDP & L2TP / IPSec IKE Port 500 UDP having L2TP payload encrypted by IPSec with UDP 4500 for NAT Traversal.