1. Assuming that your Apache server is installed at C:\Program Files\Apache Software Foundation\Apache2.2

2. Assuming that your PHP engine is installed at C:\Program Files\php-5.2.0-Win32

3. Use "notepad" to open C:\Program Files\Apache Software Foundation \Apache2.2\conf\httpd.conf

4. Go to alias_module section and define a script directory call /php/ as:

<IfModule alias_module>
...
   ScriptAlias /php/ "C:/Program Files/php-5.2.0-Win32/"
</IfModule>

5. Add an access control section for this directory as:

<Directory "C:/Program Files/php-5.2.0-Win32/">
    AllowOverride None
    Options None
    Order allow,deny
    Allow from all
</Directory>

6. Go to mime_module section and define a mime type as:

<IfModule mime_module>
...    
    AddType application/x-httpd-php .php 
</IfModule>

7. At the root level below the LoadModule section, define an "Action" entry:

#LoadModule ssl_module modules/mod_ssl.so

Action application/x-httpd-php "/php/php-cgi.exe"

This "Action" entry tells Apache to run "php-cgi.exe" from the script directory "/php/" for any "application/x-httpd-php" mime files.

8. Restart your Apache server.