PHP 5.3 on IIS gives 404 error in CGI mode

Slowly losing my mind here. I had PHP 5.2 working fine (ISAPI) under IIS, but for some extension I needed 5.3. So no worries, I installed this but it turns out ISAPI is not supplied anymore.

I followed the install tutorials for fastcgi and ended up with a 500 internal server error for every PHP page served.

So my current situation is: I have fastcgi removed. In my websites I have added PHP (head, get, post) and routed them to c:\php\php-cgi.exe.

Result: every PHP page I try (even the ones with just text) gives 404 not found error. Any HTML file I put in the same folder, serves without a hitch.

Who can help me please... How hard can something like this be right? For me apparently very hard.

Extra information:

• ran the installer as suggested below. Set it to use fastcgi.

• my fcgiext.ini file looks like this now:
  [types]
  php=c:\php\php-cgi.exe
  [c:\php\php-cgi.exe]
  exepath=c:\php\php-cgi.exe

• from the command-line a 3 line PHP file with just phpinfo(); works fine

• from the server the same PHP file with just phpinfo(); results in the internal server 500 error.
• from the server a PHP file with just text works fine
• when changing the document types in IIS management console and point the PHP extension directly to c:\php\php-cgi.exe results in 404 for every PHP file
• the php.ini is the php.ini.production file which came in the distribution. No edits were made.

Setting the IIS PHP handler directly to PHP (not via fastcgi) c:\php\php-cgi.exe results in the following:

• display a PHP page with only text....works fine
• display a page with only phpinfo(); results in 404 not found

From serverfault $pageUsers[$entry.posts[0].author].name

• Have you tried the installer .msi?

  For the rc4 of php 5.3 it's located at http://windows.php.net/downloads/qa/php-5.3.0RC4-nts-Win32-VC6-x86.msi.

  But test it on another non-productive server first. Edit: it's a release candidate anyway, so you might want to try the installer on a test-test-server...

  PP : -1 because installer results in all PHP files returning 404 error. 404 means FILE NOT FOUND. But the file exists. So this is an incredibly bad solution.
  From VolkerK

• I found the problem. In the php.ini there are some values which need to be set for CGI and IIS. The force_redirect needs to be 0. Furthermore, the PHP extension needs to be added in the webextensions sections of IIS.

  Those things fixed the problems.

  From $pageUsers[$post.author].name