I upgraded my Windows XP for all updates past SP3 and then began upgrade to Windows 7. The Windows 7 Upgrade Advisor said it did not have a driver for Parallels Network Adapter. I continued with the upgrade and sure enough, Windows 7 said it was unable to find driver for Parallels Network Adapter. The Windows 7 networking window showed no internet connectivity at all. Searching the Parallels support forums I saw something about an incompatible Systems Manager Device which was being installed during Windows upgrades which interfered with Parallels Ethernet Adapter. Did clean install of Windows XP, upgraded to SP2, then upgrade to Windows 7. Windows 7 said it was unable to find driver for Parallels Network Adapter. It turns out that was not the problem. Other support forums talked about connecting, disconnecting and connecting the Parallels Adapter in the Parallels menus. Still no joy. Confirmed Parallels tools were installed and no error messages noted. In desperation, reinstalled the Parallels tools and all of a sudden everything worked. I now have a network connection on Windows 7.