Do you want to view only the webpage content that was delivered securely?

Does Internet Explorer annoy you with this security warning?

Do you want to view only the webpage content that was delivered securely?

This message appears when you’re using a secure connection (https://) and the website is trying to load non-secure (http://) elements, too. The culprit was easy enough to find (using HttpWatch or similar tools):

HttpWatch sniffer results

What made this case unusual is that it wasn’t a server-side problem. Instead, the DivX HiQ plugin + Web Player Beta installed on the client’s machine was causing the issue on every single secure page. The warnings disappeared after uninstalling DivX HiQ (disabling the plugin should work, too):

Uninstalling DivX Web Player Beta

So, if Internet Explorer is suddenly giving you these warnings, check if you’ve recently installed DivX.