I have client who has taken it upon themselves to replace their standard ADSL connection with a bonded ADSL connection using two ISP.
I am not sure of the exact setup but basically they have 2 router - one for each of the broadband lines. They are from two different ISPs.
These routers then feed into a Draytek router to which all the clients PCs and the server are linked.
Since moving over to bonded ADSL the remote workers have been unable to establish a VPN conection to the Draytek.
The remote workers are using Windows 8.1 and PPTP.
When I try to telnet from outside the LAN to the internet on port 1723 the connection fails.
I am guessing that the first 2 bonded adsl routers are somehow blocking the VPN traffic.
I am unsure exactly how bonding works but is this likely to be the problem?