I have a customer who has a 4g USB dongle for their laptop and uses ICS to make the IP phone work, phone is plugged into the lan port on the laptop.

The users laptop died so they have a temp laptop, and when i enable ICS the ip phone works fine, normal internet browsing works fine, but PPTP vpn won't connect, and if you have the VPN connected and then enable ICS it drops the vpn tunnel after a minute or 2.

The IT guy thinks there is some other setting that needs to be done, i've spoken to my tech who set this up initially and he doesn't think there is.

Anyone got any ideas?