I have installed Windows 7 on both my computer and my wife's desktop. I am running Ultimate, and I installed Home Premium on hers. On both of these computers I have the same problem when the computer automatically reboots after a Windows Update. I don't automatically have a connection to our network. When I open the Network and Sharing Center, there are two entries under "View your active networks." One is listed as Home network, and the other is listed as Public network. In order to fix the problem, I disable the adapter and then re-enable it. Once I do this, there is only the Home network and I am able to connect to the network without any issues...

This issue occurs if you have installed network adapter driver update via Windows Update but the driver is not installed properly or corrupt because of some reasons. You may try to roll back the driver. Or just download the latest Windows 7 compatible drivers, then remove the corrupt driver and install the new drivers on both computers. Arthur Xie - MSFT

Actually EVERY TIME you "View your active networks" it shows the computer connected to a public network in spite of the fact that the checkbox to treat future networks as public is NOT checked. WIndows Homegroups are the biggest POS that MSFT ahs come up with in a long time. Every time you switch to a different router, nothing can talk to each other since EVERYTHING reverts to PUBLIC instead of WORK where it was all working fine. This automatic network detection stuff is such a horribly designed piece of garbage!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!