I am trying to pass PPTP thru to my microsoft VPN server that is behind NAT I have enabled the GRE and the PPTP connection tracking helpers.
I have also forwarded the port 1723 to the VPN server via dst-nat.
But when I try to connect with the client I get error 806, which supposedly means GRE is blocked.
I have even added a rule to the firewall to accept all GRE (for testing). Still the connection fails.
Any ideas on whats wrong here? Things to check?