OK, I tried that feature out and that definitely works.

This question is kind of related to this issue then. I have a home page that I want the visitors to come to before they have logged in. On this page I have an account login module so they can log in directly on the home page. They log in on this page and I have configured my site so it redirects them to the main page and they can never get back to the home page because it doesn't appear in the menu. I don't want them to be able to get back to this home page because it has an account login module on it and some site information and it would look strange if they could ever get back there.

However, if they close their browser but don't close all browser instances like you mentioned above then when they reopen the site, they are put onto the home page but they are still logged in. This is the problem I was trying to avoid. Is there any way to avoid this issue? (i.e. if they choose not to close all browser instances, is it possible to configure the site so that they are put on the main page when they reopen the website?)

Note: as you mentioned in the post above, if they close all browser instances then this problem is avoided. But not everyone would choose to do this.

Would this be the line in the web.config that I would want to change?

cookieName=".ASPXANONYMOUS" Cookie Name
cookieTimeout="100000" Cookie Timeout in minutes
cookiePath="/"

What would be a small enough timeout value to do a decent job of disguising the issue?

Also, if I were to put in the code about the sliding expiration in that URL you sent, where in the web.config file is it placed exactly? I'm not familiar with C# or the .NET languages unfortunately...

Thanks.