Purchased a new Gateway DX4831-01E on 4/10/10. Has onboard Intel 82578DC GB NIC. Worked fine until Sunday, when computer said no internet connector was available. Troubleshooter says driver issue. Device Mgr says card is enabled and working. Found newer driver and updated - no change. Thinking it was the NIC, I got a new Intel CT GB NIC - installed fine, Win 7 found driver newer than that on the disk that came with the NIC. Device Mgr says card is enabled and working properly. Tried to test new card from Tab under Properties - says TCP/IP Protocol not configured. Did PING 127.0.0.1 - all good.
Network Troubleshooter says the same thing for the onboard and the new NIC: "There may be a problem with the driver for Local Connection x."
I am at a loss. I have been running my home network for years, am at least an "advanced" user, yet I have no idea what is going on here. Ideas??