Unexpected network failure

I have a problem with a W2K PC on a 5 user network accessing the internet via a Linksys DSL router, but the curious part is that this PC can access files and printers on the internal network though. I ran ipconfig /renew and receive the following error message: “Unexpected network failure or insufficient access”. I was login as Administrator. I cleared all the IPs assigned by the router. I uninstall and reinstall the TCP/IP protocol. Thanks in advance for your assistance.