Vista sees multiple networks in network center
Drop to a command prompt
type ROUTE PRINT
in normal situations you should only have 1 Persistent route
this is what I had
Network Address Netmask Gateway Address Metric
0.0.0.0 0.0.0.0 10.0.0.120 Default
0.0.0.0 0.0.0.0 10.0.0.254 Default
I simply used ROUTE DELETE 0.0.0.0 10.0.0.120
disabled and enabled my NIC and all went back to normal.
you may need to delete any IPV6 routes also.
You would think that microsoft would have the stupid diagnose tool
actually investigate the routing table!