So you’ve discovered to your absolute horror that the WordPress site your company has inherited is running on Windows… on IIS?
Before you stand up, throw your computer chair out the Window, maliciously eat your co-workers salad and enjoy it, or drop all the production databases, relax. We’ve got you covered.
🤷 What’s the problem?
Good point. IIS (Information Internet Services) is the home-grown proprietary (for now) web server provided by Microsoft for Windows customers. IIS is fantastic at what it does, and can serve as an efficient web host as well as an absolutely golden reverse proxy server.
So what’s the problem?
Zilch. Nada. No dice. WordPress is absolutely not designed to be run on IIS and probably never will be. This doesn’t mean your server is going to burst into flames when you run the site, but means that when support is needed you can be damn well sure your first bit of advice will be “don’t use Windows”.
So don’t use IIS? Simple?
Except that currently NGINX is crippled on Windows (source), and Apache, which is thankfully available on Windows via unofficial channels… But you still have very little support since it operates differently being on Windows.
However, WordPress requirements state:
– so don’t lose hope just yet.
⚙️ Setting up WordPress
First you will need a database. It is recommended you have the database on a different server for performance and security reasons, but you can also have MySQL running on the same server as IIS.
MySQL runs well on Windows, and is very well supported. You shouldn’t expect much push-back in the way of configuring MySQL. However, if you wish to use Microsoft SQL Server, you may wish to check out Project Nami.
Once completed, setup a database and access user like you would a Linux-based setup installation.
Also, while it’s best to always be running the latest version of Windows Server, please consider using a version no later than IIS 10 (Windows Server 2016). This is because older versions of IIS do not have support for HTTP/2. Technically speaking the minimum requirement is IIS 7 (Windows Server 2008).
🐘 PHP on Windows/IIS
You will need to configure IIS to use CGI processing for IIS (which isn’t enabled on default IIS installations).
PHP is fully supported on Windows. To download PHP, visit their website at windows.php.net. You will also need the C++ Redist 2019 which is found on the sidebar on their website downloads.
This guide will use FastCGI, which will require a Non-thread safe version (NTS) of PHP. Typically the first download listed in each PHP version on their site will be the ideal version for IIS.
Download the correct zip file and extract it to a place of your choice on your server (Program Files is acceptable). My choice is normally C:\PHP\X.X.X (version number).
If you’re planning on running any PHP tools such as WP-CLI, it would also be a good idea to add the above path to your system Path environmental variable.
To do so, open Run (Win key + R), and run
rundll32 sysdm.cpl,EditEnvironmentVariables. Append the path to Path found under System variables.
Installing WP-CLI (optional)
PHP Manager IIS Plugin (recommended)
There is a plugin for IIS called PHP Manager, which is able to do most of the heavy-lifting for you in configuring PHP. This will enable you to register new PHP versions, adjust plugins, edit configurations and even split containers to different IIS versions as simply as possible via GUI.
Simply download their extension and install it on your server. When you next run IIS you will find a new PHP module on the snap-in.
You can register a parent PHP version and it will affect all children sites. If you register an alternative version on a child site, it will over-ride the parent and so on, in a hierarchical manner. Multi-version PHP, hooray a benefit!
PHP Manually (experienced)
If you opt not to go for IIS manager (not a fan of community IIS modules), then you can still go ahead configuring PHP manually to the IIS container.
First you need to tell the FastCGI system about your PHP installation.
- Open IIS.
- Click on the root server (just below Start Page on the left pane).
- Open FastCGI Settings.
- On the right hand side, click on Add Application…
- In Full Path, navigate to php-cgi.exe in your extracted php setup.
- In Monitor changes to file, set this to your php.ini file.
- Click on … on the end of the row named Environmental Variables.
- Click Add.
- Add PHPRC variable with the value of the PHP installation path, where your PHP-CGI file was above.
- Create another variable named PHP_FCGI_MAX_REQUESTS, and match it to the value in Instance MaxRequests (recommendation for both is 10000).
- Click OK.
Cool! IIS now knows that your PHP folder is a CGI process, it now knows how to handle requests to PHP with this processor. Now let’s set up the individual website to use PHP CGI.
- Find your container in IIS (e.g. Default Web Site) and click it.
- Open Handler Mappings.
- On the right-hand side, choose ‘Add Module Mapping‘.
- Add the following entry:
- *.php for Request Path.
- FastCgiModule for Module.
- Path to your PHP CGI for Executable.
- Whatever you want for Name.
- Head back, and go into Default document.
- Add index.php to the list (your choice).
- Test in your browser if PHP loads up.
- Try index.php file with
- Try index.php file with
If you do the above for the topmost entry (normally your machine name), it will copy to all new containers, so you don’t need to do this process for each site.
Recommended php.ini Configuration
The perfect php.ini configuration is very much a game of trial and error. Believe me, it’s difficult to find the best config balance when it comes to PHP, WordPress and Windows. Here are some essentials:
cgi.force.redirect = 0(essential!).
fastcgi.impersonate = 1
extension_dir = <Absolute path to install>/ext
These are set when using PHP Manager. This configures PHP to understand that it is operating via CGI mode. The second configuration also helps to link the PHP operations into how IIS works, enabling better interop between PHP and IIS.
The third is recommended especially if your PHP installation is not located on the C drive. Absolute stops PHP trying to interpret where the extension dir is, which is can get very wrong if not located on the C drive.
Setting up WordPress
Now for an easy part – the WordPress installation! Thankfully this is as easy to do, if not easier than the Linux server counterpart.
Create your desired site in IIS. If you’re binding this a domain or subdomain, create a new site. Otherwise, you can create a subfolder (or virtual subfolder) in IIS to setup a subfolder WordPress installation.
In the folder you bound to the container, extract the WordPress installation zip (or use WP-CLI if installed earlier). If done correctly when you visit the URL in the browser you will see the good ol’ 5 minute installation screen.
Run through the installation as per a normal site, and congratulations – you have a WordPress site running on IIS!
I received an error: 500 The FastCGI Processed exited unexpectedly.
Each version of PHP for Windows depends on a Visual C++ Redist package, which is mentioned in the download title. Normally recieving this error means your system does not have the one it needs, causing the CGI process to error.
In each download segment on the downloads website, check for VCXX (X being numerical). The left-hand sidebar will tell you which redistributable package you need and how to obtain it. Once installed, this error will stop.
If – for whatever reason – you are installing the Legacy 5.6 releases, download the 32-bit redistributable, regardless of your server architecture type.
Pretty Permalinks, and .htaccess
WordPress is smart enough to know it’s on IIS, so when you go to adjust permalinks instead of creating .htaccess, they will create a web.config file, which is the IIS equivalent. If you need additional rules the IIS rewrite module can attempt to parse your htaccess file in the IIS module.
If you create a .htaccess file, it will be ignored – IIS rewrite can attempt to convert these files, but not use them.
How do I set permissions?
The container will default to using the account IUSR, which won’t have access rights by default. For starting out, you could simply give IUSR full permissions to the folder, and your website will work. Updates will occur, cache will write, all gold.
This sometimes does not work, in which an alternative you can do is change Anonymous authentication in Authentication on the container to Application Pool identity, and give IUSRS group full access.
Both of these are not recommended for production use, as in the event of a compromise the hacker will have full write access. You can check out the guide on permissions from WordPress, as the permission fundamentals are similar.
How do I enable HTTP/2?
HTTP/2 is only supported in IIS 10 or above, which requires Windows Server 2016 or higher.
How do I increase the runtime limits?
In PHP Manager, on the container you wish to adjust, click on Set runtime limits. This will show the php.ini config options to quickly change these limits. For everyone else, you can find the limits within php.ini like always.
If you wish to increase the maximum execution time, please note that both PHP and IIS track timeouts differently. As well as increasing this via either PHP Manager or php.ini, you will need to tell IIS too.
Pop over to the root (underneath Start Page on the left panel in IIS). Open FastCGI Settings, and find the CGI you wish to modify. Click edit, and you should see two settings called Activity Timeout and Request Timeout. Set these both to whatever limit you want, and make sure all three (inc. PHP’s max_execution_time) match. Your timeout should now be sufficiently increased!
Should I choose Windows over Linux for WordPress?
No. Absolutely not.
Can I hook WordPress into Microsoft SQL Server?
Project Nami is a fork of WordPress that is designed to work with Microsoft SQL Server in place of MySQL. This team has replaced all MySQL functionality and added some beneficial functionality from SQL Server. This is well worth checking out!
Article was updated 2nd March 2020 as FastCGI configuration for manual mode was not covered.