Depending on what browser you are using, you may see a warning message even though you have enabled SSL.
Chrome - Your connection to this site is not fully secure
They will show a “Not Secure” warning for all pages served over HTTP, regardless of whether or not the page contains sensitive input fields.”
Firefox - Connection is not secure
This browser explains that this message comes up because the “HTTPS page you visit includes HTTP content, the HTTP portion can be read or modified by attackers, even though the main page is served over HTTPS. When an HTTPS page has HTTP content, we call that content “mixed”. The page you are visiting is only partially encrypted and even though it appears to be secure, it isn't.”
Internet Explorer - This webpage contains content that will not be delivered using a secure HTTPS connection, which could compromise the security of the entire webpage. OR Only Secure content is displayed.
According to IE, this message is telling you that there may be both secure and non-secure content on the page. Secure and non-secure content, or mixed content, means that a webpage is trying to display elements using both secure (HTTPS/SSL) and non-secure (HTTP) web server connections. Internet Explorer blocks non-secure content by default and is set to prompt you when this is happening.
Safari - No warning message.
This browser does not show a warning for normal mixed content websites. However, select site options (such as forms) may trigger a warning.
What all these error messages mean is that somewhere on your site, you are referencing HTTP content (e.g. HTTP instead of https). This is usually introduced by a code you have added to your site either through the HTML widget or through a code you’ve placed in the Tracking area.
To resolve these errors, you need to go through your codes and replace any instances of HTTP with https. If your widget no longer works as a result of changing over to https, this indicates that the code you are using doesn't support secure URLs. You will need to find an alternative third-party code to use.
Please note: any third party content you add to your site should be securely hosted, regardless of whether or not SSL is enabled on your domain. This will ensure that your content displays in all browsers and your visitors will not receive any security warnings. Browsers are going to become increasingly strict in this regard, so the best approach is to ensure that all content on your site is secure (https).