IIS 4.0

I’m installing IIS 4.0 on NT server with SP6 but for some reason I can’t get the web server working. When I go the browser and type http://loccalhost it reply page can’t display and down below it said HTTP 500 – internal server error internet explorer. How do i fix this problem. Please help. The reason I stay with IIS 4.0 is because my boss dont want to upgrade to server 2003 and IIS 6.