I have this EXACT same issue, however my situation might be slightly different..I have a networking program called LogMeIn Hamachi, that basically creates a LAN over the internet for you to connect with your friends and stuff (I use it to run dedicated minecraft servers...). I haven't been using it lately, so I turned off the program, however it still connects to the network. Then it gets "confused" once in a while and tries to get internet through the network, so I have to disable that network by going to "change adapter settings" in the Network and Sharing center.. On a laptop btw, don't know if that makes a difference in this case.