Fix: Vista Detects Multiple Networks With Local Only Access When Only One Cable Is Plugged In
I have had this problem for a long time now and finally found a fix for it. I'm not quite sure why Microsoft has done nothing on it. The issue seems to be that Vista has stored 2 gateways but you only have one like ever other normal person. You can run ipconfig at the command prompt to check if you want. You should find a section called default gateway. If you have two IPs listed there then you have a problem. Run "route delete 0.0.0.0" at the command prompt and that should fix it. Other people have has success with disabling IPv6 as well.
Houston we have a problem:
Default Gateway . . . . . . . . . : 0.0.0.0
10.103.35.1
I found the solution here.
