Lost Internet Connectivity; Connected to "Unidentified Network"

I had Win7 32-bit running on a Dell PC. About one week ago, I noticed Internet connectivity was gone and that there was "limited connectivity" as I was now connected to an "unidentified network".
The other systems on the network are still connected and working perfect; the problem is isolated to this one system. The network uses a static IP scheme. "IPCONFIG /ALL" shows that the IP is assigned, is included on the correct subnet and has the correct gateway and DNS information.
I've tried a host of solutions suggested on forums; from "route delete 0.0.0.0" to disabling my firewall to configuring for a dynamic IP. Nothing has worked. Reluctantly, I resorted to a fresh install as I began to worry that I may have picked something up.
I completely wiped the hard drive and did a fresh Win7 32-bit installation all only to have the same problem. I assume that the NIC is functioning as it accepts all IP settings.
Any suggestions?