If your visitors are receiving “mixed content” warnings when visiting your SSL-protected site, it’s likely that some pages are calling content (such as images, media files, or even scripts) from external locations over a HTTP connection (rather than HTTPS).
You can resolve these issues manually by searching through your site’s HTML code for HTTP hyperlinks and switching them to HTTPS. However, for WordPress, the Really Simple SSL plugin can automate discovery and resolution, making fixes quick and easy.
To install the plugin, log in to the WordPress administration dashboard and select Plugins > Add New. Search for Really Simple SSL, then click Install Now to proceed.
Once installed, click the Activate button to enable the plugin.
Read the guidance on screen and be sure to take a backup of your site before enabling SSL. When you’re ready, click Go ahead, activate SSL. You’ll then need to log back in to your WordPress site.
This feature dynamically fixes insecure content by replacing all http:// URLs with https:// (except hyperlinks to other domains), saving you potentially hours of work. You may still have to manually search for external URLs that are causing mixed content issues.
Click Settings > SSL to review the Really Simple SSL settings. Ensure Mixed content fixed was successfully detected on the front-end is checked.