Lost TCP/IP transport

I am running W2K Server on a small home network. All of a sudden I got error message on booting that TCP/IP networking transport is not installed. I tried to delete the TCP/IP protocol in my InternetRouter connection so I could reinstall it. Got error message saying you can not do this - must first uninstall WINS, QoS etc. Reinstalled W2K and Service Pak 1 and got still same problem. Checked to see that tcpip.sys is in win32 drivers and it is. The Service Pak 1 version is slightly larger. Tried to delete the network connection for InternetRouter in Safe Mode but was denied. I also have a LocalLan network which works just fine. Only the Internet access network connection fails.

Network protocals are tied to the card, so try removing the NIC in the network neighborhood, then remove the protocals.
Then re-install the nic and protocals, see if it goes. If not, you may have a bad nic.