Internet and Intranet is not working at a time………

I have two LAN Cards in my PC. One LAN card has Internet Connection. Another LAN Card is connection to the Intranet (Local). Both have Default Gateway. When I try to connect to browse any page, it shows connection not available and an exclamatory sign in taskbar network. Internet LAN have Real IP in its interface (Static).
That IP can be accessed from WAN side. But, I can't connect to the WAN from my PC. Is there any solution for this problem????
Thank You.
