Can’t connect to internet or lan. XP Home

OK, here goes. I have a client’s computer. After 14 trojans were removed, the internet connection failed. O/S was reinstalled. Upgraded to SP2. Firewall disconnected. Tried a new NIC. Configured w/static IP. Upgraded router firmware. Changed workgroup name. Tested cable. Rescanned for viruses and spyware. Changed dns – you get the idea. No connection to the internet. Cannot ping. IP stack appears OK. Any help appreciated.