Did you install Really Simple SSL on your site, and now some images, stylesheets, or external services are not loading?
When a site is requested over the SSL protocol (https), the browser will block all resources that are called with the (insecure) http protocol. This is called “mixed content” or “insecure content”. To fix this, the Really Simple SSL plugin changes all URLs to https://. If you have resources on other domains, that do not have a valid SSL certificate, these images or scripts will not load. The result can be a partly broken site.
In most cases, this is caused by an old “staging URL”. This URL was used during development, but the URLs are still in place and function without issue while on the http protocol. But on https this domain will not work, so you’ll have to change this domain to your new domain.
In other cases, the resource might be an online service with a script running from the service’s domain; so the online service should provide the resource over https. In very rare instances, you might encounter services that don’t. The recommendation in such cases would be to ask your service provider to enable SSL.
Read this step-by-step article on how to track down mixed content.
