OpenVPN routes not added on Vista
From WikiTechia
Routes are not added in Vista, and hence limited or no connectivity to the VPN.
Solution
Add the following into the config (you openvpn config usually ending in .ovpn and located in C:\Program Files\OpenVPN\config),
route-method exe route-delay 2
and run OpenVPN GUI or OpenVPN as an administrator (right-click on OpenVPN GUI and click Run as Administrator).

