Today something very strange occurred and since I wasted far too much time on it I thought I’d better write it down. I started my machine and noticed I didn’t have any internet access but I could see other machines on the network. Looking at the Networking control panel (Open Network and Sharing Center) I could see that my LAN was showing a ‘public unidentified network’. After a lot of head scratching I went to the ‘Troubleshoot Problems’. Selected the ‘Internet Connections’ and requested it check my connection to the internet. It ran and told me my DHCP was not set, and went ahead and set it for me. Suddenly my Work Network reappeared and everything was good. I’ve no idea what had reset the DHCP settings but the resolution was easy enough.