IE : Security Warning Message

When you browse to a page through HTTPS, sometimes you might get a popup similar to this :

The main reason for this is your page refers to some link which is HTTP and not HTTPS i.e. not using a secured protocol.

To resolve this:
1. Make sure every external link you are using is HTTPS
2. All your internal links should be relative


Change
div#header {
background-image: url(http://www.example.com/images/header.png) no-repeat;
}

To:

div#header {
background-image: url(/images/header.png) no-repeat;
}

3. Make sure all the IFRAME have src attribute set and points to some HTTPS or relative url. If you can't specify any url, add a blank html page in your application and specify the src to point to that page.

i.e. <IFRAME src="/../blank.html"/>