Explorer will not connect to Internet

I have a Windows ME System that is on a network with 2 other computers. It connect to the Internet via a fast cable connection through a router. All thee system can see each other on the network and share recources. Two of the computer can get onthe Internet. One system is not able to connect the the Internet. All three systems are running ME. I have uninstall & reinstalled the network, Changed setting in TCP/IP DNS etc., dowloaded trouble shooting from MS – all no help. There is no firewall on the system other than the router. The problem started after a Palm Top was installed and uninstalled. Any help will be appreciated.