What's with: "Do you want to view only webpage content that was securely delivered?"

What’s with: “Do you want to view only the webpage content that was securely delivered?” dialog box, that goes on to say:
“This web page contains content that will not be delivered using a secure https connection, which could compromise security for the entire webpage”.

I have a valid SSL, yet when the webpage is viewed, with https at the beginning of the url, images are missing, etc., but when viewed, with http at the beginning of the url, the page looks as it was designed to look.

What’s the remedy?

Are the images also coming from an https address?
AFAIK, every file referenced in an https page needs to come from https (including CSS images) else you get those nasty warnings.

[font=calibri]This happens when you are serving a page over https, but that page is calling images, scripts or other bits and bobs over http. Your browser knows that it’s a secure page, and then sees that there are loads of other items being proffered that are not on a secure server, and they are therefore a potential security risk.

The solution? It’s very easy – just put all the images, scripts and everything else on the secure server and then you can send them over https as well.[/font]

Thanks for the replies. Now I’m wondering if I need an SSL cert at all. I’m going to post another question in regard to this.