Really Simple SSL checks if there is a valid SSL certificate, and if it can find the marker from the mixed content fixer in the html of your website. In some cases the request does not receive a valid response. This can have several causes:
Server or plugin security blocks the request
If the front-end of your website loads without any issues, this is probably the case in your situation. The warning is a false positive and can be safely ignored. A false positive can occur on some hosting environments where the hosting provider doesn’t allow the plugin to retrieve the webpage.
Does the front-end return a warning or error? Please follow the steps below to diagnose and fix the issue.
Invalid SSL certificate
The no response from webpage notice also shows when Really Simple SSL cannot load your homepage over SSL. This is often caused by a misconfiguration on the server or an invalid SSL certificate. This can be tested with the Qualys SSL Labs test tool. This test will return a lot of information about the currently used SSL certificate, including any errors or misconfigurations. The test should return a grade A.
Really Simple SSL cannot obtain or install an SSL certificate for you. The plugin is a tool to configure your site for SSL and requires a valid SSL certificate before it can work correctly. If your site has an invalid SSL certificate we recommend to obtain a certificate at your hosting provider, they can help you install the certificate which is often the fastest and easiest solution. Once a valid certificate is installed, Really Simple SSL will be able to detect it and the warning should disappear.
Other possible causes
The Qualys SSL Labs test tool can return a number of different errors. For example, a ‘no secure protocols supported’ error. This error indicates that the server cannot be reached on port 443, the SSL port. This is often happens because of a misconfiguration on the server and can be fixed by your hosting provider.
If you get this error: cURL error 60: SSL certificate problem: unable to get local issuer certificate, you are probably using an older PHP version. Please upgrade your PHP to the latest version to fix this issue.
If you are unsure what to do next or have any questions in relation to this error, send us a support request.