IIS 4.0 Page cannot be displayed error.

When accessing the IIS4 Sp6a web server from another computer on the internet I recieve the msg that web page cannot be displayed. Getting the following in IE5.0 “Cannot find server or DNS Error”. On server itself web page comes up fine. Can ping and resolve IP from anywhere(client and server), only web page cannot be displayed. DNS entries are correct. All services report they are running. No HTTP error message is given (no 404’s).