I made this site with VSD http:///www.nannerch.com but when I try and use the address bar to view it, I get the warning attached. How can I prevent this?

VSD does not allow you view a site online. It try's to open above your site address. You will have to make the site a favourite in a browser. Try that. View it that way.

I can only replicate the warning message when I try to access your site using "https://..."
Did you - perhaps accidentally - add the 's' to 'http' when you typed the address?
Take a look at this help message from Firefox: http://support.mozilla.org/en-US/kb/Thi … 0untrusted

Nice-looking site, by the way!

Why are there three http:///

Presumably just a typo. But the browsers don't really mind, and choose to interpret the three slashes as two anyway...