Connect the server using vpn

I finished a win app which user can input data off line. User can use vpn to connect server to upload data.
Now, boss want me to add a feature to auto connect to server using vpn once user start the app.
Can someone give me an idea where to find out more resources to do it?

What VPN software are you using? If it is the built in Windows VPN client then you can automate it using Windwows APIs - if it is some third party software like Cisco VPN or SonicWall VPN Client then I think you may be a bit stuck..