Getting WordPress running on WinXP was surprisingly easy. Here are my notes on the install.

• WinXP SP2
• PHP 5.1
• MySQL 5.0
• WordPress 2.0

Installing PHP on IIS

• Download and install the PHP Windows installer package. I used all the default options.
• Grant IUSR_ write access to c:\php\sessiondata and c:\php\uploadtemp
• Added index.php as a default document in IIS (IIS Admin -> Default Web Site -> Properties -> Documents tab -> Add… -> index.php
• To test the install create a file named c:\inetpub\wwwroot\test.php with the contents
  [php]
  phpinfo();
  ?>
  [/php]and then use your browser to view the page at http://localhost/test.php
• Open c:\windows\php.ini
  Uncomment the line extension=php_mysql.dll
  Change the extension_dir line to read: extension_dir = "./ext/"
  Save the file.
• Download the PHP binaries (not the windows installer version).
  Extract libmysql.dll and ext/pgp_mysql.dll into c:\php and c:\php\ext

Installing MySql

• Download and install MySQL. I used the complete version but in hindsight I probably only needed the essentials.
• Download and install MySQL Administrator from the same site.

Create a WordPress database

• In the Catalogs section, create a new schema named wordpress
• In the User Administration section, create a user named wp_user, enter a password.
• Right-click on the new user, Add Host From Which The User Can Connect, enter localhost.
• Select localhost which should now appear under the new user on the left.
• On the right-hand side, select the Schema Privileges tab, select the wordpress database.
• Click the << button to assign this user full access to the wordpress database. Warning: Be sure to select the localhost node on the left when assigning privileges so the user only has permissions when connecting locally.

Setup WordPress

• Download WordPress.
• Extract to c:\inetpub\wwwroot\wordpress
• In the new wordpress folder, rename wp-config-sample.php to wp-config.php.
• Edit the file and change the database name, user name and password.
• Open your browser to http://localhost/wordpress/wp-admin/install.php
• Download themes and extensions.
• I had to peform this fix before I was able to upload files.

Enable Permalinks in WordPress with IIS

• Create a file wp-404-handler.php with the code
  [php]
  $my_wp_url = "http://" . $_SERVER['SERVER_NAME'] . "";
  $_SERVER['REQUEST_URI'] = substr($_SERVER['QUERY_STRING'], strpos($_SERVER['QUERY_STRING'], $my_wp_url)+strlen($my_wp_url));
  $_SERVER['PATH_INFO'] = $_SERVER['REQUEST_URI'];
  include('index.php');
  ?>
  [/php]
  This code is from WordPress Permalinks on IIS. I have changed the code slightly (line 2) since I host my Wordpress installation in the root directory.

• Configure IIS to redirect 404 errors to “/” (no quotes)
• UrlScan, must be configured to allow periods in the URL. Open c:\windows\system32\inetsrv\urlscan\urlscan.ini. Change option to read AllowDotInPath=1
• Turn on permalinks in the WordPress permalinks options
• Restart IIS

Some other good articles on setting up WordPress, PHP, MySQL:
David Seah’s WIMP Notes
WordPress 5-minute install
Web Thang Installing PHP for IIS on Win XP
WordPress Permalinks on IIS
Easy Permalinks in IIS