When setting up a VPN, you can run into quite a few problems like what authentication it needs, which password do you use. If you are using a Virgin Media SuperHub you have the added challenge that by default your speedy SuperHub will block outgoing VPN traffic meaning that with all the correct details it just doesn't work. To fix this, just follow the below steps:
- Browse to your SuperHub's IP Address (e.g. 192.168.0.1) and log in
- Select "Advanced Settings" and click "Yes" to confirm you want to view these
- Select "Firewall" from the list
- Tick "IPSec Pass-Through", "PPTP Pass-Through" and "Multicast Pass-Through" at the bottom of the page
- Click "Yes" to confirm settings change
- Try to connect your VPN again.
This allows the traffic through for VPN authentication and should now allow your VPN to connect as normal.
Source : http://community.virginmedia.com/t5/Up-to-30Mb-Setup-Equipment/vpn-access-not-working-with-new-super-hub-box/td-p/2027284