Internet access Problem possibly gateway

I have a small network, peer to peer, a Gnet Internet gateway attached to the main switch for the network. All desktops are fine with the internet access except 1 which is a Windows ME Hp 7920. It will access Internet for browsing, but cannot get out to update Virus scan nor will it connect to Isp for e-mail. Yet all others on the network have no problem with either of these events. Looking for any ideas.