New PHP installation problems

[pacman99]

Hey,
I'm new to installing php. I had it running fine under linux (FC5) as it was pretty straightforward but on Windows 2003 Server I'm having some problems.
I installed php4 isapi on my IIS 6.0 server. I gave cmd.exe internet guest account priviledges. And the internet guest account has read/execute permissions for the server as well. IIS is told to run "scripts and executables" but when I try to run ANY php script, I get no output. I either get errors like:
[code]Notice: Undefined index: PHP_AUTH_USER in Z:\web\www\bismillah\UT\scripts\frontend\index.php on line 61[/code]

or I get no output at all. These scripts worked fine under FC5, php4.
What am I doing wrong?

Thanks~