I have two W2K server machines with the same symptoms:
When I open the Start->Settings->network connection folder, all network connections have disappeared. This condition remains for a considerable long time, and is persistent over several reboot cycles
The network connections are still functional, and I have made minor changes (IP address) since then by directly modifying the registry, but I have no chance to regulary manage the settings.
The connections are still visible with "ipconfig /all".
The account I use has admin privileges, so the connections should not be hidden by any rules.
OS upgrade is not an option, reinstall of the OS definitely not preferred ... =:S
Any hint ?