Sometimes hidden devices can exist as objects in the Device Manager. When these are NICs, and sometimes monitors and other things, problems can occur. To see these, do this:
- Open Command Prompt. Then enter:
set devmgr_show_nonpresent_devices=1
devmgmt.msc
- When the Device Manager comes up as requested by #3, there will be a “View” menu. Open the View menu, and choose “Show Hidden Devices”.
The problem can be especially significant in Server 2003, after a devirtualization; the NIC devices used during virtualization are probably still there, and very possibly, still active in the OS to a startling extent. One server we saw was exhibiting an IP conflict until removal, presumably through the 127.0.0.* subnet.