Yesterday as I was about to apply updates to a Windows 2003 application server running Apache, the NIC stopped sending packets. No updates were done. Checking the NIC status, you see the packets coming in, but the sending number stays constant. After rebooting, the sending number reaches approx. 700 and then all sending stops. I can ping the loopback and the machine by IP and name. When I ping the gateway, I get "destination host unreachable." When I look at the ARP table on the switch, the switch can see the machine but it cannot ping it (the machine will send one packet to the switch). I have verified the settings on the card (static IP). I have disabled the card and re-enabled it. I have uninstalled the card and re-installed it. I have plugged the cable into a different switch port. I have swapped out the network cable. I have verified the switch configuration. The firewall service is not running. I have shut down the HBSS . I verified the HBSS logs and they were clean. I checked the system and application logs and there are no events that have anything to do with the netwok issue - only errors after the network went down. I have run a Symantec full scan and it was clean. I have installed a USB NIC - the problem happens on this new NIC as well. One really weird item: I disabled the USB NIC and re-enabled it, and even though I have a static IP, the card is trying to use DHCP. I have done everything I can think of to track down the problem. Can anyone help with other suggestions before I attempt a repair of the OS?