1. Log into your server through Terminal Services or Remote Desktop Connection.
2. Open a Web browser and load http://www.php.net/downloads.php
3. Download the Windows PHP5.x ZIP package.
4. Create a new directory, c:\PHP.
5. Unzip the file you downloaded above into c:\PHP.
6. Create a new directory, C:\PHP\phpsessions.
7. Right click the C:\PHP folder and select Properties.
8. On the Security Tab click Add.
9. Type IUSR_COMPUTERNAME (where computer name is the name of your computer) in the text area, click Check Names and then click OK.
10. Select the IUSR_COMPUTERNAME user, check the Full Control box and click OK.
11. Open C:\PHP\php.ini-dist in Notepad.
12. Within the file, make the following replacements:
    • Replace ;extension=php_mysql.dll with extension=php_mysql.dll
    • Replace ;session.save_path = “/tmp” with session.save_path = “C:\PHP\phpsessions”
    • Replace session.gc_maxlifetime = 1440 with session.gc_maxlifetime = 43200
    • Replace SMTP = localhost with SMTP = smtp.yourdomain.com
    • Replace ;sendmail_from = me@example.com with sendmail_from = user@yourdomain.com
13. Save the file as C:\windows\php.ini.
14. Copy C:\PHP\libmysql.dll and C:\PHP\ext\php_mysql.dll to the C:\windows\system32 folder.
15. Open IIS located under Control Panel -> Administrative Tools -> Internet Information Services (IIS) Manager.
16. Right click Web Service Extensions and select Add a new Web service extension.
17. Enter php as the Extension Name, check Set extension status to Allowed and Click Add.
18. Enter the path to C:\PHP\php5isapi.dll and click OK.
19. Right click Web Sites and select Properties.
20. On the ISAPI Filters tab, click Add.
21. Enter php as the Filter Name, enter C:\PHP\php5isapi.dll as the Executable and click OK.
22. On the Home Directory tab, click Configuration.
23. Click Add.
24. Enter C:\PHP\php5isapi.dll as the Executable, enter php as the Extension and click OK.
25. On the Documents Tab, click Add.
26. Enter index.php and click OK.
27. A popup box may appear asking if you want to apply the settings to certain websites. Choose specific websites to enable PHP on or Select All and click OK.
28. Right click your Computer Name, expand All Tasks and click Restart IIS.
29. Choose Restart IIS from the dropdown menu and click OK.

*Make sure the permissions to your PHP folder have “NETWORK SERVICE”, “IUSR_*”, “SYSTEM” included.* If not php will not load!