vpn through 2600 with firewall

[chris.byers]

I am having a good deal of trouble getting a pptp connection established through a 2600 series router with access lists. As someone else set up this router, and due to the fact that I am fairly unfamiliar with the cisco firewall commands, could someone steer me in the right direction?

I am able to start the connection (i.e., it starts trying to authenticate), but the ppp tunnel is unable to be established back through the router.

[mike-greene]

Make sure that you have an access list that permits tcp port 1723 to your pptp server. The command should look something like this "ip access-list 101 permit tcp any host 192.168.2.2 eq 1723"

[kasey.hohenbrink]

you will also need to allow the protocol GRE as well at the IP tcp port 1723.

PPTP is based on GRE tunneling and uses port 1723 to setup the signalling.