I’m rebuilding my company’s website around WordPress, but a sticking point is a web contact form. This appeared to be no problem as there’s several nice contact form add-ins for WordPress. However, it didn’t matter which one I used, Contact Form 7, Fast Secure Contact Form, Contact ColdForm, they all didn’t work. I’d hit submit and the page would cycle back (or in the case of CF7, the spinning arrow would just sit there forever). I rebuilt the server by importing the theme and WordPress settings in a different website and the forms worked, until I restored the MySql database.

At that point I knew it had to be one of the dozens of customizations I had done to WordPress that was causing the forms to fail. And after a bit of a search, I found it: my custom permalink.  It turns out that although most of the rest of WordPress is forgiving about not rewriting URLs, the contact forms are not.  This was on IIS7 so I had to download and install the URL rewrite module and then follow the somewhat cryptic instructions here.