Microsoft IIS / PWS

This section contains notes and hints specific to IIS (Microsoft Internet Information Server).


By using the CGI setup, your server is open to several possible attacks. Please read our CGI security section to learn how to defend yourself from those attacks.

General considerations for all installations of PHP with IIS

Windows NT/200x/XP and IIS 4 or newer

PHP may be installed as a CGI binary, or with the ISAPI module. In either case, you need to start the Microsoft Management Console (may appear as 'Internet Services Manager', either in your Windows NT 4.0 Option Pack branch or the Control Panel=>Administrative Tools under Windows 2000/XP). Then right click on your Web server node (this will most probably appear as 'Default Web Server'), and select 'Properties'.

If you want to use the CGI binary, do the following:

To use the ISAPI module, do the following:

With IIS 6 (2003 Server), open up the IIS Manager, go to Web Service Extensions, choose "Add a new Web service extension", enter in a name such as PHP, choose the Add button and for the value browse to either the ISAPI file (php4isapi.dll or php5isapi.dll) or CGI (php.exe or php-cgi.exe) then check "Set extension status to Allowed" and click OK.

In order to use index.php as a default content page, do the following: From within the Documents tab, choose Add. Type in index.php and click OK. Adjust the order by choosing Move Up or Move Down. This is similar to setting DirectoryIndex with Apache.

The steps above must be repeated for each extension that is to be associated with PHP scripts. .php is the most common although .php3 may be required for legacy applications.

If you experience 100% CPU usage after some time, turn off the IIS setting Cache ISAPI Application.

Windows and PWS 4

PWS 4 does not support ISAPI, only PHP CGI should be used.

Windows and PWS/IIS 3

The recommended method for configuring these servers is to use the REG file included with the distribution (pws-php4cgi.reg in the SAPI folder for PHP 4, or pws-php5cgi.reg in the main folder for PHP 5). You may want to edit this file and make sure the extensions and PHP install directories match your configuration. Or you can follow the steps below to do it manually.


These steps involve working directly with the Windows registry. One error here can leave your system in an unstable state. We highly recommend that you back up your registry first. The PHP Development team will not be held responsible if you damage your registry.

The following steps do not affect the web server installation and only apply if you want your PHP scripts to be executed when they are run from the command line (ex. run C:\myscripts\test.php) or by double clicking on them in a directory viewer window. You may wish to skip these steps as you might prefer the PHP files to load into a text editor when you double click on them.

PWS and IIS 3 users now have a fully operational system. IIS 3 users can use a nifty tool from Steven Genusa to configure their script maps.