Well, the reinstalling was unnecessary because there are plenty of ways to reload the MS bootloader, but that's beside the point..
In order to help you, as Poert said, we gotta have any error messages or something to tell us what happens. We can't tell you why it might not run without symptoms. If you try to run it, does nothing ever appear? Do you get a splash screen? Does it start then go away like a crash? Anything?
Also, might check the netscape directory and see if there's a .log file- if there is, it might provide clues.