Seriously.... I have one network card (Built in on my ASUS P5N-D mobo), hooked up to one router, hooked up to
one cable modem. Most of the time, it works great, but from time to time, it connects to a second network. "Home" is my standard network, and if I can't connect to the internet, I'll go to network connections, and it will show "Home - Connected" and "Unidentified Network - Connected," and I have zero connectivity at that point. I know how to fix this*, but I don't know what's causing it.
*Disable one connection (both connections disappear and it disables my network card as well), then go into Device Manager, re-enable my network card, and it usually fires right up and works fine. What gives?
Also, no wireless network card, so it's not picking up a random wifi network.