This problem has been plaguing me for some time, but it's finally time to fix. I can enter a static IP/mask/gateway/DNS which Vista will use even across reboots. However, each time I view my IP configuration information in the GUI it shows "Obtain automatically" for both IP and DNS. ipconfig /all reports DHCP Enabled: No. Although annoying, it's harmless until I want to temporarily add a secondary static IP (for router configuration in a different subnet). I can add the secondary IP by re-entering my primary static IP/DNS info, then follow normal procedure for the secondary. However, when it's time to remove the secondary IP, all configuration is gone as usual but that includes the secondary IP. The only way I can remove it is by editing the registry. I have compared the registry keys in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\{GUID} to a working Vista machine to no avail. I've also updated to the latest driver for my NIC as suggested in a post on a similar topic. This issue smells like a registry problem, but I'm not sure where else to look. For what it's worth, this is a Dell desktop with Vista32 and the NIC is an Intel 82562V-2 10/100 with driver version 9.13.41.0.

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