Add Expire headers in Asp.net
<p>I am using YSlow to grade the performance of my application and I got an D grade for the Add Expires Header aspect.</p>

<p>I am using IIS express, so I found this code online and added it into the web.config file but it doesnt work; the grade is still D.</p>

<p>I did it in the web.config file. Any idea how to improve the grade of "Add Expires Header" ?</p>

<pre><code>    &lt;system.webServer&gt;
   &lt;staticContent&gt;

&lt;clientCache cacheControlMaxAge="30.00:00:00" cacheControlMode="UseMaxAge"/&gt;

&lt;/staticContent&gt;
</code></pre>