My new Windows 2000 server came with an integrated 100Mbps Ethernet adapter. I want to swap the existing NIC with an Intel Gigabit Ethernet adapter. I've had no trouble adding the new adapter and disabling the old NIC. However, when I try to set the IP address, I receive an error message that tells me the IP address I entered is already assigned to another adapter.

I can continue, but I can't join my Windows NT 4.0 domain. (This machine was on the NT 4.0 domain before I swapped adapters, but during my struggle, I removed the machine from my existing domain.) If I use DHCP, I can add the machine to the domain without difficulty. How can I avoid this situation?

This situation is a good example of a relatively easy task in NT 4.0 that has become a hidden and difficult task in Win2K. Let's start with the IP address problem. You can get the error message you refer to even when you simply move the NIC from one PCI slot to another. To do away with the annoying message, you must delete the old NIC from Win2K Device Manager. Open a command-prompt window and enter the commands

set devmgr_show_nonpresent_
devices=1

start devmgmt.msc

The first command permits Device Manager to show phantom devices; the second command launches Device Manager. From Device Manager's menu bar, select View, Show hidden devices. Expand the Network Adapter node, and delete the old adapter.

As for the inability to join the domain unless you select DHCP, several factors could be at fault. First, WINS could be responsible. Your PDC or BDC might be reading from WINS that your machine is at another IP address. Go to your BDC or PDC and try to ping the new server. If the BDC or PDC tries to ping the server at the address you assigned with DHCP, the quickest way around the problem might be to create an LMHOSTS file for the server. You should also look at the NetBIOS cache on your PDC and BDC. At the command line, type

nbtstat -c

If an entry for the new server references the DHCP-assigned IP address, you need to flush your cache. To do so, type

nbtstat -R