What did you expect to happen?

Configure the plugin. Open the wizard and clicked next and expected it to work.

What happened instead?

When I clicked next after opening the wizard I was prompted to authenticate. From the web server logs the plugin is trying to put this and can't: PUT /wp-json/yoast/v1/configurator

For grins I gave security to a login, used that and the prompt went away but nothing happened then when I clicked next.

How can we reproduce this behavior?

Install the 3.6 version of Yoast SEO on a Wordpress site hosted on a server using IIS.

Technical info

• WordPress version: 4.6.1
• Yoast SEO version: 3.6