I have recently run into a strange problem with my main Windows Vista Ultimate system and my networking. So far both times that it happened to me were after Windows automatically applied Windows Updates and rebooted. The machine is based on an Intel Board with an Intel on board Gigabit Nic. It has been more of an issue lately as with my back injury (I can’t sit down) I have been using remote desktop to connect from my laptop down to my main machine to use some applications or access data.
I have tried to connect via remote desktop back to my machine but the desktop would not respond. I checked the machine and it was powered up and sitting at the log in screen. Logging in and checking the networks showed that the machine was connected to two networks, my own (private) and an unidentified network (public). There is only 1 network adaptor and no Bluetooth or wireless in this machine. Furthermore it was showing local only as connectivity.
Running diagnose and repair indicated that there were two network connections and to disconnect 1 and try again. Disconnecting the cable did no good. The first time this happened it solved itself after a reboot, when it happened today two reboots did not solve the problem. Finally I disabled the network card and re-enabled it and this solved the problem.
I am still not sure if this was caused when the machine rebooted when remote desktop was connected or if there was another reason. I will watch it a little more closely and see if the problem crops up again.