Trying to access install.php leads to 500 - Internal server error. Help!!

[machinus]

I can access other files, such as the license.txt for example. I have made sure my php.ini has the correct settings according to the readme. I am an admin and this is a dedicated machine, so I am not sure why I would be having permissions problems. Here is the error report:

Error Summary
HTTP Error 500.0 - Internal Server Error
C:\Program Files\PHP\php-cgi.exe - The FastCGI process exited unexpectedly

Detailed Error Information
Module FastCgiModule
Notification ExecuteRequestHandler
Handler PHP_via_FastCGI
Error Code 0x000000ff
Requested URL *********/install.php
Physical Path C:\inetpub\wwwroot\install.php
Logon Method Anonymous
Logon User Anonymous

Most likely causes:
•IIS received the request; however, an internal error occurred during the processing of the request. The root cause of this error depends on which module handles the request and what was happening in the worker process when this error occurred.
•IIS was not able to access the web.config file for the Web site or application. This can occur if the NTFS permissions are set incorrectly.
•IIS was not able to process configuration for the Web site or application.
•The authenticated user does not have permission to use this DLL.
•The request is mapped to a managed handler but the .NET Extensibility Feature is not installed.

I have put UAC to the lowest level but I am not sure if there is something else I need to to get this to work properly. Is FastCGI the right thing to be using?

[Kermit]

Did you try to chmod instal.php as 777 ? and does it happen the same,when you just browse the url,where you uploaded your smf files ?