I installed expires header at IIS 7.5 but still do not show at Firefox firebug yslow or .net plugin

I did setup like this

but result is still like this:

Where do I make a mistake?

it was casued by google analytics code. i had to setup this way

var _gaq = _gaq || []; _gaq.push(['_setAccount', 'UA-xxxxxxx-1'], ['_setDomainName', 'www.xxxxxxx.com'], ['_trackPageview']开发者_JS百科);

Of course the expires header won't show.

You have set up the webserver to expire content "after 14 days".

This will result in "Cache-control: max-age=xxxx" header. Not the "Expires" header.